Short-duration Cultivars Research Articles

Strategic cultivar and sowing time selection for weed management and higher redgram productivity in semi-arid Indian regions

IntroductionRedgram (Cajanus cajan L. Mill sp.), a leguminous crop commonly grown in tropical and subtropical climates, is highly valued for its high protein content (21%), which contributes significantly to food and nutritional security. However, its production faces challenges primarily due to terminal dryness experienced during critical growth stages because of changing rainfall patterns. To overcome this, adaptive techniques become imperative as the productivity of this crop is intricately linked to environmental factors and the crop’s growth cycle.MethodsHence, the field experiment was conducted at the National Pulses Research Centre, Vamban, Pudukkottai, Tamil Nadu, in South India under rainfed condition, during the kharif (monsoon) seasons of 2017–18 and 2018–19. The primary objectives were to determine the optimal sowing time and identify suitable redgram cultivars, especially in the context of the late onset of the monsoon in Tamil Nadu, a common issue under changing climate conditions. The experiments tested six different sowing dates with three redgram cultivars.Results and discussionThe findings highlighted the substantial influence of different redgram cultivars and sowing times on the crop’s growth characteristics and yield. Among the six sowing dates tested, planting in later half of June (S6) resulted in notably higher plant height (201 cm), a greater number of pods per plant (287), a seed yield of 1,112 kg ha−1, and a benefit-cost ratio of 2.61 Notably, this sowing period (S6) demonstrated comparable performance with the treatment of redgram sowing in the latter part of September (S4). CO 6 (V1) is the most productive of the three redgram cultivars, with the highest mean pant height (200 cm), number of pods per plant (237), grain yield (1,017 kg ha−1), and benefit cost ratio (2.38). Extended phenological phases along with extra days to reach phenological stages could account for the increased yield in comparison to the other cultivars. Among the two short-duration cultivars, VBN (Rg) 3 (V3) had a significantly higher mean grain yield of 958 kg ha−1 with the benefit-cost ratio of 2.24. Even though CO 6 (V1) obtained a higher yield due to its long duration nature, it matured in 187 days whereas VBN (Rg) 3 (V3) matured within 129 days. Consequently, the short-duration redgram cultivars emerge as highly suitable choices for integrating into crop sequences, thereby augmenting farm cropping intensity.

Agrometeorological indices, physiological growth parameters and performance of finger millet as influenced by different cultivars under hot and sub humid region of Odisha

Present-day agriculture is under tremendous pressure due to various factors such as climate change, degradation of soil and water quality, and yield plateauing of major food crops. Under these scenarios, there is an urgent need to choose a climate-resilient and ecologically hardy crop which can perform under adverse conditions with low input requirements. In this regard, millets can be suitable crops for agricultural sustainability. Among various millets, finger millet (Eleusine coracana L. Gaertn) is cultivated mainly in India and Africa. However, most farmers grow finger millet with local cultivars, and improved ones can be replaced to enhance productivity. The present investigation conducted at the Post Graduate Research Farm of Centurion University of Technology and Management, Odisha, focused on evaluating suitable cultivars of finger millet. The study revealed that cultivars significantly influenced finger millet growth, productivity, and economics. The physiological growth parameters, namely, crop growth rate, relative growth rate, net assimilation rate and leaf area duration were significantly influenced by finger millet cultivars. The growing degree days (GDD), helio-thermal units (HTU) and photothermal units (PTU) of the finger millet showed a great variation among the cultivars. The Maximum total GDD (2169 °C day), HTU (18141 °C day hours) and PTU (24297 °C day hours) were recorded in the cultivar Hima(w) VR 936. The cultivars Indravathi VR 1101, Sri Chaitanya VR 847 (1.73) and Hima (W) VR 936 (1.60) were superior to other cultivars in expression of the grain yield and economics of finger millet. The study concluded that the cultivation of Indravathi and Sri Chaitanya could be considered as short-duration cultivars; however, Hima can be chosen as long duration crop for successful finger millet cultivation with higher net returns and benefit-cost ratio under hot and sub-humid regions of Odisha.

Generation Change of Cropping Intensity in Bangladesh: A Systematic Review

The cropping intensity in Bangladesh remained stagnant until the late 18th century, then surged notably during the period of 1987–88 and 2010–11. Cropping intensity increased from 143% to 173.06% with an annual growth rate of 1.20% in the first half of Bangladesh's 50 years of independence. During that period, net cropped area fell from 8248.16 thousand hectares to 7806.07 thousand hectares, while gross cropped area increased from 11785.55 thousand hectares to 13518.64 thousand hectares.
 In the second half of 50 years, cropping intensity has increased from 173.06 to 198.00 with an increasing rate of 0.99% per year, in this time both net and gross cropped area increased. Overall, within the 50 years of Bangladesh's independence, cropping intensity has increased from 143% (1971-72) to 198% (2019-20) with an increasing rate of 1.10% per year and will be 211.03 % (projected) by 2030. At that time net cropped area decreased from 8248.16 thousand hectares to 8126.00 thousand hectares but grossed cropped area increased from 11785.55 thousand hectares to 16057.00 thousand hectares. This overall change in cropping intensity is due to an increase in double (17.11%) and tripled cropped area (18.37%) and a decline in single cropped area (-35.76%). Shifting from single to multiple cropping attributed to this change. New short-duration cultivars tailored to fallow time drove intensity. However, limited climate-smart solutions and management practices posed hindrances. Examining rice yield extension, this study used historical and projected trends to forecast 2030 cropping intensity. New four cropped-based CP has also been introduced which occupied 0.28% of the net cropped area and definitely will play a vital role to increase cropping intensity in the future.

Comparison of Short-Duration and Long-Duration Rice Cultivars Cultivated in Various Planting Densities

The selection of high-yielding, short-duration rice cultivars is essential for the double-rice cropping system. High hill density could be achieved with less labor under machine transplanted conditions. Therefore, dense planting is more practical for machine-transplanted rice. While few studies have been conducted to certify the feasibility of short-duration cultivar combined with dense planting in machine transplanted conditions. The current study was executed to determine the effects of dense planting on yield attributes and grain yield of short-duration cultivars under mechanically transplanted conditions. A field experiment comprises two treatments—i.e., the short-duration cultivar Lingliangyou104 cultivated at a high planting density (SDH) and the long-duration Taiyou390 cultivar cultivated at a low planting density (LDL)—were conducted in the 2018 and 2019 late seasons. The results showed that the SDH exhibited 17% and 19% higher panicle number in a unit, 26% and 24% higher spikelet filling, 8% and 8% higher grain weight, 21% and 11% higher harvest index, and consequently 12% and 4% higher grain yield and 13 and 15 days shortened growth duration compared to the LDL in the 2018 and 2019, respectively. The data revealed that the difference in grain yield between the SDH and LDL was mainly due to the higher harvest index and reasonable dry matter distribution of the SDH, which was conducive to improving yield components and increasing rice grain yield. As a result, short-duration rice cultivars combined with dense planting is a feasible strategy for improving the grain yield of mechanically transplanted late rice.

Source–sink relationships in short-duration and hybrid rice cultivars in tropical Asia

Shortening the period of rice cropping enables farmers to reduce irrigation water in tropical lowlands. However, grain yield of tropical short-duration rice is often restricted by poor grain filling, whose causes are yet unknown. This study evaluated the source–sink balance, which is closely associated with grain filling, in tropical rice. We compared the percentage of filled grains and stem nonstructural carbohydrates in a popular short-duration cultivar and a high-yielding hybrid cultivar over a wide range of spikelets m −2 by differentiating the N inputs and planting densities on a lowland farm of the International Rice Research Institute, the Philippines, during four seasons. Grain yield ranged from 2.2 to 8.6 t ha −1 , with the hybrid cultivar producing consistently higher yield (by 27% on average). Compared with the hybrid cultivar, the short-duration cultivar had less stem nonstructural carbohydrates at heading per spikelet (by 24% on average) and a lower percentage of filled grains in the wet season (by 13% on average), when the source capacity was lowest. Source capacity per spikelet and stem nonstructural carbohydrates at heading per spikelet were significantly associated with the percentage of filled grains, suggesting that these indicators of the source–sink ratio modulate grain filling in tropical rice. Although the sink capacity of the short-duration cultivar was similar to, or smaller than, that of the hybrid cultivar, its limited source capacity resulted in poorer grain filling. We suggest that the role of stem nonstructural carbohydrates should be emphasized in the breeding of tropical short-duration rice. • Increase in spikelets/m 2 does not increase yield in tropical short-duration rice. • Grain filling was poorer in short-duration rice than hybrid rice in wet seasons. • Source capacity and stem nonstructural carbohydrate were related to grain filling. • A high source-to-sink ratio with high stem nonstructural carbohydrates is needed.

Evaluating the impact of intra-seasonal change in temperature and solar radiation on phenology and yield of rice using CERES-rice model in Punjab

Rice is a staple food of global as well as Indian population and its productivity is vulnerable to climate change. Keeping in view the observed trends in climate variability, phenology and yield of rice were simulated using CERES-Rice model under climatic scenarios of changes in temperature (+0.5, +1.0, +1.5, +2.0, +2.5, +3.0 °C from normal) and solar radiation (+2.5, +5.0, +10.0, +12.5, +15.0, +20.0% from normal) and their combined interactive effects during differential growth periods, i.e., whole season, vegetative phase, grain filling phase, 0-30 days after transplanting (DAT), 30-60 DAT, 60-90 DAT. In general, with a rise in temperature from normal, the CERES-Rice model predicted advancement in phenological development in rice and vice versa. In general, the increase in yield of rice cultivars for different transplanting dates was observed with decrease in temperature and increase in radiation and vice-versa. With rise in temperature from normal, CERES-Rice model showed maximum decrease in grain yield of rice during whole season change followed by grain filling phase change and vegetative phase change in decreasing order. Among the growth periods, maximum decrease in yield was observed in 0-30 DAT (early vegetative) followed by 30-60 DAT (late vegetative) and 60-90 DAT (grain filling) in decreasing order. Under the conditions of heat and radiative stress, grain filling phase and early vegetative phase was more vulnerable. The CERES-Rice model predictions showed that rice cv. PR-118 (long duration cultivar) was more tolerant to heat and radiative stress than cv. PR-115 (short duration cultivar) and hence may be recommended for cultivation due to its tolerant traits towards maintaining its good grain yield and harvest index.

Modeling the effects of elevation and precipitation on Rice (Oryza sativa L.) production considering multiple planting methods and cultivars in Central China

In this study, we investigated the effects of elevation and precipitation on rice (Oryza sativa L.) production using the Crop Environment Resource Synthesis (CERES)-Rice model in Hubei province, China. We divided our study area into four zones based on elevation and precipitation. For each zone, our simulations were conducted using three planting methods: dry direct-seeded rice (DDSR), wet direct-seeded rice (WDSR), and transplanted-flooded rice (TFR), with three rice cultivars of different growth duration: Yangliangyou6 (long-duration), Huanghuazhan (mid-duration), and Lvhan1 (short-duration). Additionally, the optimal irrigation strategy for WDSR was determined with the CERES-Rice model. Our results indicated that the yields of WDSR with the optimal irrigation strategy were comparable with those of TFR in low-elevation regions but were less than the TFR yields in high-elevation areas. Furthermore, the rice yields increased at first and then decreased with increasing elevation, which was affected by growing period length and photosynthesis rate. Compared with the other two cultivars, the short-duration cultivar may be more suitable for growing in high-elevation regions. In addition, high precipitation could facilitate the cultivation of the long-duration cultivar in low-elevation regions, as it gives DDSR a yield potential comparable to that of WDSR for the short-duration cultivar in high-elevation regions. This study could help farmers choose optimal field management practices based on elevation and precipitation, ensuring sustainable and improved rice production.

Physical and mechanical properties of cassava (Manihot esculenta Crantz) cultivars: Implications for the design of mechanical peeling machines

AbstractThe data on physical and mechanical properties of short and long‐duration cassava cultivars are limited to design an efficient continuous type peeling machine for small‐scale processing. Short duration cultivars included Sree Jaya, Sree Vijaya, and Sree Swarna, as well as long duration cultivars included M‐4, Sree Athulya, Sree Suvarna, H‐226, Sree Raksha, Sree Pavithra, and Sree Vishakam, were investigated. The moisture content, girth, proximal diameter, middle diameter, cylindricity, and tuber surface taper angle were the highest for long‐duration cultivar H‐226. The maximum length was observed in the short‐duration cultivar Sree Swarna. The periderm thickness was the highest for Sree Suvarna, whereas the highest proximal cortex thickness, middle cortex thickness, and distal cortex thickness were observed in Sree Athulya, Sree Vijaya, and M‐4 cultivar, respectively. The highest bulk density, true density, and porosity were observed in the long‐duration cultivars; Sree Raksha, Sree Athulya, and Sree Suvarna, respectively. The highest hardness, shear force, and rupture force were recorded for cassava peelings in the cultivar Sree Athulya. Similarly for cassava flesh, the highest hardness, shear force, and rupture forces were recorded in the Sree Suvarna cultivar. A strong positive correlation for true density with bulk density and proximal diameter and moisture content with cylindricity and middle‐end diameter was found from the multivariate correlation analysis. Statistical analysis showed that the reported physical and mechanical properties of the cultivars were highly significant (p <.01).Practical ApplicationsEngineering properties such as physical and mechanical properties are important for designing machines, storage structures, and processes. Cassava tuber peeling by the manual method is time‐consuming, labor‐intensive, and has a low capacity. Thus, the design of a peeling machine for small‐scale processing becomes important. The physical and mechanical characteristics of cassava flesh and peelings are critical design considerations for developing peeling machines for small‐scale processing. The physical and mechanical properties investigated here would provide technical and scientific data for designing continuous shearing type cassava peeling machine units such as tuber feeder length, peeling knife selection, peeling knife angle, and adjustable spring with required tension for holding rotary type peeling knife.

Impact of Genetic Improvements of Rice on Its Water Use and Effects of Climate Variability in Egypt

Developing and disseminating resilient rice cultivars with increased productivity is a key solution to the problem of limited natural resources such as land and water. We investigated trends in rice cultivation areas and the overall production in Egypt between 2000 and 2018. This study identified rice cultivars that showed potential for high productivity when cultivated under limited irrigation. The results indicated that there were significant annual reductions in both the rice-cultivated area (−1.7% per year) and the production (−1.9% per year) during the study period. Among the commonly cultivated varieties, Sakha101 showed the highest land unit productivity, while Sakha102 showed the highest water unit productivity. The impact of deploying new cultivars was analyzed by substitution scenarios. The results showed that substituting cultivars Giza179 and Sakha107 has the potential to increase land productivity by 15.8% and 22.6%, respectively. This could result in 0.8 million m3 in water savings compared to 2018 water consumption. Long-term impacts of climate variability on the minimum and maximum temperature, relative humidity, and average precipitation during on- and off-season for rice productivity were also analyzed using an autoregressive distributed lag (ARDL) model. The results indicated that climate variability has an overall negative impact on rice productivity. Specifically, minimum temperature and on- and off-season precipitation had major long-term impacts, while higher relative humidity had a pronounced short-term impact on rice yields. The study revealed that short-duration cultivars with higher yields provided greater net savings in irrigation resources. These analyses are critical to guide the development of strategic management plans to mitigate short- and long-term climate effects on overall rice production and for developing and deploying improved rice varieties for sustainable rice production.

Alteration in agronomic practices to utilize rice fallows for higher system productivity and sustainability

• Successful diversification of fallows depends on agronomic manipulation in kharif. • System productivity was increased from 3−5 to 5.5–7.6 t ha −1 by diversification. • Rice yield may be low in dry-DSR but as a system it is profitable and sustainable. • Yield is high in long duration cultivar but net returns and B:C ratio was low. • Diversification with pulses improved soil health, productivity and profitability. Rainfed rice agro-ecosystems play an important role in food production, and there is a huge scope for utilizing residual moisture in rice fallows to cultivate short-duration and low input demanding crops. However, the success of crops grown on rice fallows largely depends on the method and cultivars of rice adopted. Therefore, we examined the performance of wet season rice under different establishment methods by using different cultivars, as well as the impact of those wet-season rice treatments on post-rice crops grown during the rice-fallow of rainfed lowlands of eastern India. Rice yield was significantly higher under transplanting during all years of study, and Swarna-sub1 yielded more than the short duration cultivars (Naveen and Sahbhagidhan) due to its higher yield potential. However, transplanting the rice crop negatively affected the performance of dry season crops grown during the rice fallow; crops taken after dry-DSR (direct seeded rice) yielded more, and use of short duration cultivars in the wet season increased the yields of toria, greengram and blackgram in dry season by 37.9, 40.4 and 36.1 %, respectively. Although rice yield under dry-DSR was lower than when transplanted, the advantage of dry-DSR was the higher yield of dry season crops, resulting in almost similar system productivity to that of transplanted rice. The long duration cultivar was not profitable; although the yield was high, as a whole system the net returns and B:C ratio were as low as 5–10 % for Swarna-Sub1.The diversification of rice fallows improved the soil health in terms of fertility status, carbon fractions, microbial population and soil enzymatic activities, with more beneficial effects observed when legumes were planted. In the rice-legume systems, build up of N, P and K was 10, 24 and 7 % higher, respectively, and soil enzymatic activities were10–25 % higher, as compared to the rice-toria system. Based on the results of our study, it is recommended that short duration cultivars can be cultivated using dry-DSR in rainfed rice areas, so that a legume crop (greengram/blackgram) can be cultivated after the rice crop to achieve higher profitability, system productivity, and sustainability in the long run.

Additional Income Generation from Cultivation of Summer Mungbean in Rice-Wheat System of Haryana

Background: Mungbean [Vigna radiata (L.) Wilczek], also known as green gram is cultivated on area of 4.75 million ha in kharif and rabi/ spring seasons as monocrop or intercrop in India. It serves as a major source of dietary protein for the vast majority of vegetarian people in the country. Mungbean contributed 10.03 per cent of total pulses production (23.40 million tonnes) in the country with productivity level of 494 kg ha-1 in 2018-19. The pulses cultivation in Haryana is almost eliminated in kharif season owing to deviation of area towards cotton, cluster bean and pearlmillet because of low profitability. However, the new window opens for cultivation of mungbean in rice-wheat cropping system in summer season to generate additional farm income and to improve soil health. The area under summer mungbean in state was around 64 thousand ha with the production of 50 thousand tonnes and the average productivity of 780 kg/ha during 2017-18. Although rice-wheat system provides better farm returns, but it has imposed threat to soil health, availability and contamination of ground water, weed and biotic stress management. Methods: The data pertains to costs and returns from summer mungbean cultivation was gathered from 60 mungbean cultivators of Hisar, Kurukshetra and Panipat districts of Haryana having adequate irrigation water availability adopting personal interaction approach in 2018-19. Simple budgeting technique was employed to draw practical implications which ultimately help to take favourable policy decisions for enhancing acreage of summer mungbean. Result: The inquiry profound that mungbean cultivation in summer season particularly in rice-wheat was established as additional income generation farm enterprise. The net benefits accrued from short duration varieties of mungbean over variable cost was Rs. 31831 ha-1 with time span of 60-70 days by utilizing fallow land in summer season. The B-C ratio toiled considering expenses incurred on variable resources with value of 2.99 divulges economic viability of mungbean cultivation in the study area. It is imperative from results that cultivation of short duration cultivars of mungbean is viable option to enhance farm income, restoration of diminishing soil fertility owing to adoption of continuous rice-wheat rotation by inherent characteristics of converting atmospheric nitrogen. Distinctive efforts are essential to evolve mungbean cultivars suitable to prevailing cropping system in Haryana and assure market procurement. The exploration of mungbean cultivation will reduce dependency on import and improve net availability of pulses in India.

Utilizing Wild Cajanus platycarpus, a Tertiary Genepool Species for Enriching Variability in the Primary Genepool for Pigeonpea Improvement.

The use of crop wild relatives in the breeding program has been well recognized to diversify the genetic base along with introgression of useful traits. Cajanus platycarpus (Benth.) Maesen, an annual wild relative belonging to the tertiary genepool of pigeonpea, possesses many useful traits such as early maturity, high protein content, photoperiod insensitivity, and pod borer tolerance for the genetic improvement of cultivated pigeonpea. Using this cross incompatible wild Cajanus species, an advanced backcross population was developed following the embryo rescue technique. In the present study, a pre-breeding population consisting of 136 introgression lines (ILs) along with five popular varieties (used as checks) was evaluated for important agronomic traits during 2016 and 2017 rainy seasons and for grain nutrient content during 2016, 2017, and 2018 rainy seasons. Large genetic variation was observed for agronomic traits such as days to 50% flowering, number of pods per plant, pod weight per plant, grain yield per plant, and grain nutrients [protein content, grain iron (Fe), zinc (Zn), calcium (Ca), and magnesium (Mg)] in the pre-breeding population. Significant genotype × environment interaction was also observed for agronomic traits as well as grain nutrients indicating the sensitivity of these traits to the environments. No significant correlations were observed between grain yield and grain nutrients except grain Zn content which was negatively correlated with grain yield. Overall, 28 promising high-yielding ILs with high grain nutrient content were identified. These ILs, in particular, ICPP # 171012, 171004, 171102, 171087, 171006, and 171050 flowered significantly earlier than the popular mega variety, ICPL 87119 (Asha) and thus hold potential in developing new short-duration cultivars. The comprehensive multi-site assessment of these high-yielding, nutrient-rich accessions would be useful in identifying region-specific promising lines for direct release as cultivars. Moreover, these ILs are expected to replace the popular existing cultivars or for use as new and diverse sources of variations in hybridization programs for pigeonpea improvement.

Elastic sowing dates with low seeding rate for grain yield maintenance in mechanized large-scale double-cropped rice production

Elastic sowing dates (ESDs) are correlated with rice grain yield. ESD is the easiest factor for farmers to manipulate in mechanized large-scale farming. In this study, field experiments were conducted over a 2-year period to determine the effects of different sowing dates on growth duration, effective accumulated temperature, and yield attributes in two early- and late-season machine-transplanted rice cultivars. In early rice (ER), a delay in the sowing date led to decreased grain yield and shorter growth duration. In late rice (LR), delayed sowing led to significantly lower grain yield and prolonged growth duration. In LR, significantly positive correlations were detected between effective accumulated temperature in the post-heading stage and both filling ratio and yield. Reproductive redundancy increased markedly in LR, by 7.72% over a 5-day interval. We determined that the ESDs for LR were 10 days later than the control, and that of ER was recommend early sowing rather than late sowing. These findings suggest a new strategy to meet the demands of mechanized large-scale rice farming: the development of thermal sensitive high-yield long-duration ER cultivars and high-yield short-duration LR cultivars.

Cultivar × Management Interaction to Reduce Lodging and Improve Grain Yield of Irrigated Spring Wheat: Optimising Plant Growth Regulator Use, N Application Timing, Row Spacing and Sowing Date.

Severe lodging of irrigated spring-wheat in sub-tropical Australia has previously caused yield loss of between 1.7 and 4.6 t ha–1 (20–60% of potential yield). In response, agronomic management options were assessed for their ability to reduce lodging and increase grain yield, namely plant growth regulators (PGRs), timing of nitrogen (N) application, row spacing and sowing date, in combination with long and short duration cultivars across 15 irrigated environments from 2012 to 2016. Our study identified significant interaction between genotype, environment and agronomic management (G × E × M) for grain yield and lodging, although some combinations of agronomic techniques were broadly applicable across cultivars. PGR application improved grain yield of most cultivars in well-irrigated fields that had more than 120 kg ha–1 N (mineral N + fertiliser N) at sowing, with yield gains of up to 0.5 t ha–1 observed in both lodged and non-lodged fields. However, PGRs had little effect on grain yield when soil + fertiliser N at sowing was less than 80 kg ha–1 N. In-crop N application (compared to sowing N application) often improved grain yield of short duration, lodging resistant cultivars, but reduced the yield of long-duration, lodging susceptible cultivars in some environments. Narrow row spacing of 19 cm had the highest grain yield across cultivars in low lodging environments. At a severely lodged environment, narrow rows were the highest yielding for five out of six cultivars when PGRs were used, but was the highest yielding for only half of the tested cultivars when PGRs were not used. Cultivar × sowing date interaction for grain yield was also associated with the occurrence of lodging. Neither early nor late sowing had a consistent yield benefit across a range of cultivars, as lodging severity varied between sowing date depending on the timing of storm-induced lodging events. Lodging resistant long-duration cultivars had more stable grain yield across environments and increased grain yield in response to early sowing. Further research is needed to determine the optimum management strategy for new cultivars, because farmers do not always choose the most lodging resistant cultivars for reasons of cultivar disease resistance, grain quality and seed availability.

Effects of Environmental Factors on Tulip (Tulipa sp.) Cultivars Grown in West Bengal Plains

To investigate the effects of environmental factors on tulip (Tulipa sp.) cultivars in the plains of West Bengal, a field experiment was conducted with ten tulip cultivars, considered as ten treatments (T) (T1=Apeldorn, T2=Maureen, T3=Holland Cich, T4=Day Dream, T5=Pussima Design, T6=Avignon, T7=Roi-du-midi, T8=Clear Water, T9=Colouch and T10=Jumbo Beauty), at Horticultural Research Station, Bidhan Chandra Krishi Viswavidyalaya, Mondouri, Nadia, West Bengal, India in two successive years of 2013-14 and 2014-15. Flower yield, flower length (cm), flower diameter (cm), plant height (cm) etc were observed and statistically analyzed and correlation was done between the morphological data and the environmental factors. The results showed that the short duration cultivars could be more suitable for cultivation under the short and mild winter conditions of the plains of West Bengal.

Agronomic management and climate change scenario simulations on productivity of rice, maize and wheat in central Nepal using DSSAT ver 4.5 crop model

Average productivity of 3.50 t/ha of rice, 2.50 t/ha of maize and 2.45 t/ha of wheat in Nepal have been very less than their potential productivity for which précised agronomic management and changing climatic scenarios have been reported the most challenging factors at present. Cropping system Model (CSM)-Crop Estimation through Resource and Environment Synthesis (CERES)- Rice, Maize and Wheat, embedded under Decision Support System for Agro-technology Transfer (DSSAT) ver. 4.5 was evaluated from a datasets of farmers’ field experimentations of the central Nepal (Terai-Nawalpur and mid-hill-Kaski districts), and showed high sensitivity of model over change in different agronomic management and climate change scenarios. Model calibration was done by using maximum attainable yield treatments for all tested cultivars while validation was accomplished by using the remaining treatments for predicting growth, phenology and yield of all crop cultivars and results were found perfectly matched with the observed results. Further, the different agronomic management options and climate change scenarios as advocated by IPCC for 2020, 2050 and 2080 from base line of 1995 was studied to simulate the growth and yield performance of diverse crop cultivars. The hybrids and short duration cultivars of all three cereals were found more affected due to climate change than the local and long duration crop cultivars. The model simulation results obtained on rice, maize and wheat using DSSAT ver 4.5 model highlighted that there is utmost importance to develop new climate ready crop cultivars to feed the future generation over different climate change scenarios as suggested by IPCC, 2007 and the simulation results should be extrapolated to the major domains of similar agro-ecozones in Nepal. It is suggested that CSM- CERES- model would be reliable and valid approach for getting strategic decision support system especially with regards to the climate change adaptation measures in Nepal.

Availability of existing early-season rice cultivars as resources for selecting high-yielding short-duration cultivars of machine-transplanted late-season rice

AbstractHigh-yielding short-duration cultivars are required due to the development of mechanized large-scale double-season rice (i.e. early- and late-season rice) production in China. The objective of this study was to identify whether existing early-season rice cultivars can be used as resources to select high-yielding, short-duration (less than 115 days) cultivars of machine-transplanted late-season rice. Field experiments were conducted in Yongan, Hunan Province, China in the early and late rice-growing seasons in 2015 and 2016. Eight early-season rice cultivars (Liangyou 6, Lingliangyou 211, Lingliangyou 268, Xiangzaoxian 32, Xiangzaoxian 42, Zhongjiazao 17, Zhongzao 39, and Zhuliangyou 819) with growth durations of less than 115 days were used in 2015, and four cultivars (Lingliangyou 268, Zhongjiazao 17, Zhongzao 39, and Zhuliangyou 819) with good yield performance in the late season in 2015 were grown in 2016. All cultivars had a growth duration of less than 110 days when grown in the late season in both years. Zhongjiazao 17 produced the maximum grain yield of 9.61 Mg ha−1 with a daily grain yield of 108 kg ha−1 d−1 in the late season in 2015. Averaged across both years, Lingliangyou 268 had the highest grain yield of 8.57 Mg ha−1 with a daily grain yield of 95 kg ha−1 d−1 in the late season. The good yield performance of the early-season rice cultivars grown in the late season was mainly attributable to higher apparent radiation use efficiency. Growth duration and grain yield of early-season rice cultivars grown in the late season were not significantly related to those grown in the early season. Our study suggests that it is feasible to select high-yielding short-duration cultivars from existing early-season rice cultivars for machine-transplanted late-season rice production. Special tests by growing alternative early-season rice cultivars in the late season should be done to determine their growth duration and grain yield for such selection.

Intervention of Climate Smart Technologies for Improving Water Productivity in an Enormous Water Use Rice-Wheat System of South-Asia

I Intensively practices rice-wheat (R-W) cropping system (RWCS) in South-Asia is suffering from many sustainability issues such as micronutrient deficiencies, labour scarcity, production cost, declining land, declining groundwater level and water productivity along with declining soil health. Climate change further complex the things in one or other way. Therefore, the intervention of climate smart technologies are urgent for improving water productivity in an enormous water use RWCS of South-Asia. Although, farmers are confused regarding picking of suitable climate smart technology (CST) viz., laser land leveling, un-puddled direct-seeded rice (UPDSR), soil matric potential based irrigation, double zero tillage in wheat followed by rice, raised bed planting, short duration cultivars and correct transplantation time, for enhancing their livelihoods through increasing land and water productivity on one side and mitigating global warming consequences on other. Performance of these technologies is both site and situation specific, and care must be taken in practicing them. Most of them cutting down the drainage losses, which further reduces recharging of soil profile which is not required in water stressed regions while these might be termed as energy-saving technologies; otherwise used to withdraw water from the deeper soil depths. These CST are also useful for waterlogged regions. However, CST viz. correct transplantation time and short duration cultivars partition higher fraction of ET water (evapotranspiration) from E (evaporation) to T (transpiration) component which further favour higher grain yields and thus, higher water productivity. Therefore, it is crucial for the introduction of CST for improving agricultural and water productivity in the era of climate change in an enormous water use RWCS of South-Asia.

Intervention of Climate Smart Technologies for Improving Water Productivity in an Enormous Water Use Rice-Wheat System of South-Asia

I Intensively practices rice-wheat (R-W) cropping system (RWCS) in South-Asia is suffering from many sustainability issues such as micronutrient deficiencies, labour scarcity, production cost, declining land, declining groundwater level and water productivity along with declining soil health. Climate change further complex the things in one or other way. Therefore, the intervention of climate smart technologies are urgent for improving water productivity in an enormous water use RWCS of South-Asia. Although, farmers are confused regarding picking of suitable climate smart technology (CST) viz., laser land leveling, un-puddled direct-seeded rice (UPDSR), soil matric potential based irrigation, double zero tillage in wheat followed by rice, raised bed planting, short duration cultivars and correct transplantation time, for enhancing their livelihoods through increasing land and water productivity on one side and mitigating global warming consequences on other. Performance of these technologies is both site and situation specific, and care must be taken in practicing them. Most of them cutting down the drainage losses, which further reduces recharging of soil profile which is not required in water stressed regions while these might be termed as energy-saving technologies; otherwise used to withdraw water from the deeper soil depths. These CST are also useful for waterlogged regions. However, CST viz. correct transplantation time and short duration cultivars partition higher fraction of ET water (evapotranspiration) from E (evaporation) to T (transpiration) component which further favour higher grain yields and thus, higher water productivity. Therefore, it is crucial for the introduction of CST for improving agricultural and water productivity in the era of climate change in an enormous water use RWCS of South-Asia.

Inter-relationship between intercepted radiation and rice yield influenced by transplanting time, method, and variety.

Photosynthetically active radiation (PAR) is one of the most important environmental factors that determine the productivity and grain quality of the crops. Continuous rainy days or cloudy weather throughout crop growth especially at critical stages often resulted in great loss of grain quality and yield in rice. Low light stress has rigorously constrained the rice production in various rice-growing regions, especially in Southeast Asia. Method and time of planting are the major management factors contributing to the higher yield potential of rice by influencing light harvesting and use efficiency. Present study was executed consecutively for 5years (kharif seasons of 2012-2016) to determine whether planting time improves the radiation absorption and use efficiency in different duration rice cultivars. We evaluated the difference in plant growth and development leading to yield formation under different planting time which related to radiation incidence and interception. The results of the study revealed that PAR interception depends on morphological characters of cultivars and also with agronomic management such as transplanting time and method. Long duration cultivar intercepted more PAR but interception decreased due to late planting (3rd week of July), whereas short duration cultivars (Naveen) when planted earlier (1st week of June) could not effectively utilize intercepted PAR constraining the biomass accumulation and yield formation. Effect of planting density and crop architecture on PAR absorption was apparent among establishment methods as light interception at crop canopy was highest in the system of rice intensification and lowest in that of wet direct seeding. In general, Pooja as a long duration cultivar intercepted more PAR per day but when compared on same date of planting, the comparative absorption of radiation was 30.6% higher in Naveen. The lower yields in the wet season are attributed mostly to reduction in grain number per panicle or per unit land area, which is a consequence of high spikelet sterility. Grain yield of rice planted in July third week was reduced by 3.8, 12.3, and 6.9% over June first and third week and July first week, respectively, mainly due to spikelet sterility (26%) and lower grains per panicle (18%). Our results indicated that agronomic management like optimum time of sowing, cultivar duration, and establishment methods should be followed for yield improvement in tropical lowlands where light intensity is limiting due to prevailing weather situations.