Rainfed Upland Research Articles

Climate change impacts on rainfed cropping production systems in the tropics and the case of smallholder farms in North-west Cambodia

The consequences of climate change on smallholder farms are locally specific and difficult to quantify because of variations in farming systems, complexity of agricultural and non-agricultural livelihood activities and climate-related vulnerability. One way to better understand the issues is to learn from the experiences of farmers themselves. Thus, this study aimed to better understand rainfed upland cropping systems in NW Cambodia and to identify practical, social and economic constraints to adoption of known climate adaptation options applicable to local agro-ecosystems. The study also sought to document the climate change perceptions and adaptation options employed by farmers to mitigate the climate risks. A household survey was conducted in the districts of Sala Krau and Samlout in North-west Cambodia in 2013 where 390 representatives of households were randomly selected for interviews, group discussions and field observations. The majority of respondents perceived that changes had occurred in the rainfall pattern such as a later start to the monsoon season, decreasing annual rainfall, increasing frequencies of drought and dry spells, and warmer temperatures. Farmers reported reductions in crop yields of 16–27 % over the five-year period of 2008–2012. However, these reductions were not evident in provincial data for the same period. Farmers claimed climate impacts resulted in significant yield reductions, but they appear not to have an effective strategy to adapt to the changes in climate. Further regional research is required to refine climate change adaptation strategies for rainfed upland cropping systems in Cambodia.

Effects of farmyard manure and activated effective microorganisms on rain-fed upland rice in Mwanza, Tanzania

The study was conducted to analyse and compare nutrient contents of farmyard manure, farmyard manure treated with effective microorganisms and effective microorganism solutions, also, to determine the effect of farmyard manure and activated effective microorganisms on rice growth, development and yield. Farmyard manure and effective microorganism solutions were characterized for nutrient status in the laboratory. A 3 × 3 factorial experiment in randomized complete block design and replicated thrice involved farmyard manure and activated effective microorganisms. Farmyard manure at rates 0, 5 and 10 t ha−1 was applied 2 weeks before sowing by broadcasting and incorporated into the soil. Activated effective microorganism solution at 0, 20 and 40 l ha−1 was sprayed weekly at vegetative stage. Farmyard manure and effective microorganism solution contained both macro- and micronutrients at varying proportions. Application of farmyard manure increased rice yields from 1.35 to 3.31 t ha−1, 1.35 to 3.03 t ha−1 activated effective microorganism solution, and 1.35 to 3.33 t ha−1 in both farmyard manure and activated effective microorganisms when integrated. Adoption of organic soil amendments would improve soil fertility for sustainable crop production to small-scale farmers.

Available micronutrient status in relation to soil properties in some villages under four agro-climatic features of West Bengal

The deficiency and toxicity range of micronutrients namely, zinc (Zn), iron (Fe), manganese (Mn), copper (Cu), boron (B) etc., in soil is narrow; therefore proper assessment of available micronutrient status in soil is very important. The availability of micronutrients under flood plain alluvial agro-climatic zone of West Bengal, India may be influenced due to the different agro-climatic features (ACF) and also variation in physicochemical properties of the soil, which may ultimately affect the optimum crop yield. With this background, available micronutrient status was assessed in fifty two topsoil (0–20 cm) at four different agroclimatic features (flood prone rainfed, undulated rainfed upland, high flood plain (diara) and flood prone situations) in four different districts (Uttar Dinajpur, Dakshin Dinajpur, Malda and Murshidabad, respectively) of West Bengal. The mean DTPA extractable Fe, Mn, Cu and Zn in these ACF were in the range of 7.118.17, 1.50–2.93, 1.04–2.03 and 0.73–0.87 mg kg−1, respectively. The available B was in the range of 0.39 0.49 mg kg−1. Among the soil micronutrients, Zn and B were found deficient by 20 and 60% soil samples, respectively. The correlation matrix of micronutrient status with different soil physicochemical properties showed that Fe, Mn, Cu and B had positive correlations with clay, organic carbon, potassium and CEC, and negative correlations with sand and pH. Zinc was significantly and positively correlated with electrical conductivity. Boron and Mn had positive correlation with soil pH and organic carbon content. Zinc had significant positive correlation with sand and significantly negative relationship with available phosphorus.

Effect of Intercropping Greengram and Blackgram in Sesame for Augmenting the Productivity and Rain Water Use Efficiency Under Rainfed Upland Condition

A field experiment was conducted during the kharif seasons of 2010, 2011 and 2012 at the research farm of All India Coordinated Research Project for Dryland Agriculture, Biswanath College of Agriculture, Assam Agricultural University, Biswanath Chariali with the objectives to find out the feasibility of intercropping green gram and black gram in sesame. The experiment was conducted with 11 treatments (T1-Sesame Sole, T2-Green gram Sole, T3-Black gram Sole, T4-Sesame + Greengram (1: 1), T5-Sesame + Greengram (2: 1), T6 Sesame + Greengram (2: 2), T7-Sesame + Greengram (3: 1), T8-Sesame + Blackgram (1: 1), T9-Sesame + Blackgram (2: 1), T10-Sesame + Blackgram (2: 2), T11-Sesame + Blackgram (3: 1).) in a Randomized Block Design with three replications. Considering the sesame as base crop, sesame, greengram and blackgram were sown simultaneously as per treatment during post kharif seasons (Mid August-Mid September). It was observed that intercropping of sesame in green gram and blackgram had significantly superior value in respect of the Sesame Equivalent Yield (SEY), Land Equivalent Ratio (LER), Rain Water Use Efficiency (RWUE) net return and B: C ratio. From the pooled data of three years, the highest SEY (13.85q/ha) was recorded by T8-Sesame + blackgram (1: 1) followed by Sesame + Greengram (2: 2) and Sesame + blackgram (2: 1). The highest LER (1.42), RWUE (7.42kg/ha/mm), Net return (39, 374/ha) and B: C ratio(4.40) was also recorded in Sesame + Blackgram (1: 1).

Identification of Key Agronomic Traits for Farmer’s Variety Selection in Rainfed Upland Rice Systems of Laos

Identification of Key Agronomic Traits for Farmer’s Variety Selection in Rainfed Upland Rice Systems of Laos

Secondary genetic productivity factors (SGPFs) in expression of grain yield in rainfed upland rice of Bastar Plateau

In present investigation, 18 new genotypes were tested for upland rainfed ecology during Kharif 2013 and 2014, to identify promising genotypes and formulate phenological relationships at phenotypic and genotypic levels with uncertain weather parameters. The test populations exhibited enough variation to carry on crop breeding research however, genotypes responded differentially to water stress and late season drought with respect to morphological and yield traits. Considering genetic secondary productivity factors (SGPF), days to flowering, plant height, panicles per unit area, spikelet fertility and harvest index was observed to be major contributors for water scarce survivals. Days to flowering was found to be negatively associated with grain yield (-0.1941, -0.2986*, -0.2586 for Kharif 2013, 2014 and pooled over environment, respectively). Grain yield was positively and significantly associated with total crop biomass (0.6669**, 0.6122**, 0.6185**), plant height (0.5059**, 0.4145**, 0.4541**) and crop duration. Biased selection for earliness cause reduction in grain yield due to shortened vegetative phase hence, research is to be focused to minimize the yield penalty associated with earliness.

Feasibility and sizing of unlined on-farm pond for partial rice substitution in rainfed uplands of eastern India

Rice (Oryza sativa L.)-dominated rainfed uplands of eastern India are facing two major problems such as lack of irrigation water sources and low productivity. In fact, unlined on-farm pond (OFP) technology in this terrain could prove to be an effective agricultural drought mitigation measure for monsoon crops but failed to ensure supplemental irrigation (SI) to the next winter crops. Consequently, the OFP technology could not pick up in the region. In order to overcome the shortcomings in the technology, the location of the OFP has been changed and a new concept of partial rice substitution (PRS) has been introduced in the present study to provide SI for the second crop in winter. Maize (Zea mays L.) and rice crops at upper and lower compartments of the field, respectively, were tried at various crop substitution ratios (CSR) of 70:30, 60:40, 50:50, 40:60, and 30:70 during monsoon season. Rainfall excess from both the compartments was harvested in an unlined OFP located in between the compartments and used for providing SI. In winter, black gram (Vigna mungo L.) and mustard (Brassica campestris) were taken in the upper and lower compartments, respectively, based on availability of water in the OFP. Water balance models were used to simulate the soil moisture in crop root zone as well as storage of water in the OFP. The optimal size of such unlined OFP for average land holdings (1200 m2) in rainfed uplands and under 60:40 CSR was found to be occupying 6 % area of the crop field.

Colonization behaviour of arbuscular mycorrhizal fungi and phosphorus uptake pattern of mycorrhizal sensitive upland paddy using hydroponics culture

Three upland rice cultivars namely Vandana, Brown Gora and Kalinga collected from the Central Rainfed Upland Rice Research Station (CRURRS), Hazaribag, Jharkhand of the Central Rice Research Institute, are mycorrhiza sensitive genotypes. Their affinity towards mycorrhizal colonization varied. The cv. Kalinga had the highest colonization followed by Vandana and Brown Gora. Variation of arbuscular mycorrhizal fungi affinity of the rice genotypes might be due to the variable demands of phosphorus nutrition of the different genotypes. To justify these variable demands of phosphorus among these three cultivars of rice, four different doses of phosphorus (5, 10, 15 and 20 ppm) were imposed to them in a system of hydroponics. Overall, among the three cultivars, the highest uptake efficiency (34% at 30 days, 57% at 45 days, 68% at 60days and 70% at 75 days interval) throughout the growth period was noticed in the cv. Brown Gora, followed by Kalinga and Vandana. The physiological demands of phosphorus of these cultivars were finally estimated as the contribution of uptake phosphorus to the total dry matter production of the plants with respect to available phosphorus. The overall results of these estimations gave the highest value in cv. Kalinga followed by the cv. Vandana and Brown Gora. Therefore, the cultivars Brown Gora and Kalinga could be recommended for the cultivation of the vast upland rain-fed areas of the country for higher yield and increased phosphorus use efficiency which could ultimately contribute significantly to the food grain production of the country.

Sustainability of rice production systems: an empirical evaluation to improve policy

An evaluation is needed to monitor the progress of sustainable development (SD) in rice production systems. The purpose of this study is to provide policy inputs, examine the sustainability of rice production, and determine major policy areas. A requisite set of 12 indicators of three dimensions of SD, namely economic, was generated by employing an assemblage of top–down and bottom–up approaches. The data were gathered from farm households’ survey as well as in-depth discussion with stakeholders from the regions that represent irrigated, rain-fed lowland, rain-fed upland, flood-prone, and saline-prone rice-growing ecosystems in Bangladesh. By constructing composite indicators, the results revealed that 44 % of rice growers were economically viable, environmentally sound, and socially developed. The irrigated rice production system was found to be the most sustainable. The path analysis measured the contribution of the indicators to the index, and results highlighted that rice growers’ knowledge, skills, and social networks development, improving land productivity, and integrated nutrient management were essential for promoting sustainable rice production. However, the study findings suggest that pluralistic (i.e., government and non-government) agricultural advisory services can serve as an engine of transition to rice production sustainability in which a multi-year planning and strategy formulation are crucial besides investing in the modernization of extension services. Overall and ecosystem-specific policy implications that emerged from the findings of this study are outlined.

Evaluation of Different Improved Upland Rice Varieties for Low Soil Nitrogen Adaptability

Scarcity of nitrogen fertilizer is a major constraint to rice production particularly in developing countries. Low soil fertility prevalent in farmer’s fields has led to low rice yields and the ever escalating fertilizer prices have made this important input unaffordable to most smallholder farmers who have limited resources for purchasing the required inputs. The Mwea Upland rice (MWUR) varieties were bred under low fertilizer input environment while other authors have indicated that the New Rice for Africa (NERICA) gives high yields under low input conditions. There is therefore need to identify the superior rice varieties that are adaptable to low nitrogen levels. Thus, the objective of this study was to investigate the effects of different rates of nitrogen fertilizer on improved upland rice varieties and identify the low input adaptable varieties. Field studies were conducted at Alupe in Western Kenya under rainfed upland conditions between August 2012 and April 2013. The experiment layout was split plot factorial in a Randomized Complete Block Design with three replicates. The main plot treatments were four rates of nitrogen fertilizer levels which were; 0 (control), 40, 80 and 120 kg ha-1 applied as calcium ammonium nitrate (26% N) in two equal splits; 21 days after sowing (DAS) and at panicle initiation (46 DAS). Sub-plots consisted of Original Research Article Sikuku et al; IJPSS, 5(1): 40-49, 2015; Article no.IJPSS.2015.058 41 four MWUR varieties namely MWUR 1, MWUR 2, MWUR 3, MWUR 4; and four NERICA varieties namely NERICA 1, NERICA 4, NERICA 10 and NERICA 11. The parameters measured included plant height, tiller number, filled grain ratio percentage and yield components. In the study, nitrogen treatment showed significant effect on plant growth and the measured parameters increased significantly with increase in nitrogen level. MWUR varieties studied were more adaptable to low nitrogen conditions as compared to NERICA varieties. The NERICA varieties recorded higher yield at high nitrogen levels as compared to MWUR varieties. However, NERICA 4 gave higher yield as compared to other NERICA varieties regardless of the nitrogen level. Results from our study suggest that MWUR 1 and 2 and NERICA 4 were more tolerant to low nitrogen as compared to MWUR 3 and 4 and NERICA 1, 10 and 11, because of higher height, more tiller number, higher filled grain ratio percentage and higher yield component as compared to the other studied varieties and may be suitable for soils low in nitrogen.

Effect of Foliar Application of Potassium on Yield, Drought Tolerance and Rain Water Use Efficiency of Toria under Rainfed Upland Situation of Assam

A field experiment was conducted during rabi seasons of 2011–12 and 2012–13 at the research farm of All India Coordinated Research Project for Dryland Agriculture at Biswanath College of Agriculture, Assam Agricultural University to study the effect of foliar application of potassium on yield, drought tolerance and rain water use efficiency of toria under rainfed upland situation of Assam. The experiment was conducted with 8 treatments (T1: Control, T2: 100% NPK (RDF), T3: 100% N & P+ 75% K as basal, T4: 100% N & P+ 50% K as basal, T5: T3+ 2% KCl spray before flowering, T6: T4+ 2% KCl spray before flowering, T7: T5+ 2% KCl spray at siliqua formation, T8: T6+ 2% KCl spray at siliqua formation) in a Randomized Block Design with three replications. Foliar application of potassium on growth and yield of toria revealed that application of 100% N&P + 75% K as basal + 2% KCl spray before flowering + 2% KCl spray at siliqua formation (T7) resulted in highest grain yield (5.66 q/ha), straw yield (10.82 q/ha), Rain Water Use Efficiency (16.23 kg/ha mm−1), net return ( 9341 ha−1) and B:C ratio (2.15).

Response of rice (Oryza sativa) varieties to different levels of nitrogen under rainfed upland condition of Mizoram

A field experiment was conducted during 2012 and 2013 at Kolasib District of Mizoram on the response of rice (Oryza sativa L) varieties to different levels of nitrogen. Plant height and dry matter production were the highest with ‘Bhalum 3’ at 90 kg N/ha. Panicles/m2, filled grains/panicle, grain (4.50 tons/ha) and straw yield and nitogen uptake by grain and straw were also significantly higher with ‘Bhalum 3’. Increasing levels of nitrogen enhanced panicles/m2, filled grains/panicle, grain and straw yield and nitrogen uptake by grain and straw only up to 90 kg N/ha. Varieties and nitrogen levels interacted significantly and the highest grain yield and economics were recorded with ‘Bhalum 3’ at 90 kg N/ha and it was found to be optimum combination for upland rice.

Do NERICA rice cultivars express resistance to Striga hermonthica (Del.) Benth. and Striga asiatica (L.) Kuntze under field conditions?

The parasitic weeds Striga asiatica and Striga hermonthica cause high yield losses in rain-fed upland rice in Africa. Two resistance classes (pre- and post-attachment) and several resistant genotypes have been identified among NERICA (New Rice for Africa) cultivars under laboratory conditions (in vitro) previously. However, little is known about expression of this resistance under field conditions. Here we investigated (1) whether resistance exhibited under controlled conditions would express under representative Striga-infested field conditions, and (2) whether NERICA cultivars would achieve relatively good grain yields under Striga-infested conditions. Twenty-five rice cultivars, including all 18 upland NERICA cultivars, were screened in S. asiatica-infested (in Tanzania) and S. hermonthica-infested (in Kenya) fields during two seasons. Additionally, a selection of cultivars was tested in vitro, in mini-rhizotron systems. For the first time, resistance observed under controlled conditions was confirmed in the field for NERICA-2, -5, -10 and -17 (against S. asiatica) and NERICA-1 to -5, -10, -12, -13 and -17 (against S. hermonthica). Despite high Striga-infestation levels, yields of around 1.8tha−1 were obtained with NERICA-1, -9 and -10 (in the S. asiatica-infested field) and around 1.4tha−1 with NERICA-3, -4, -8, -12 and -13 (in the S. hermonthica-infested field). In addition, potential levels of tolerance were identified in vitro, in NERICA-1, -17 and -9 (S. asiatica) and in NERICA-1, -17 and -10 (S. hermonthica). These findings are highly relevant to rice agronomists and breeders and molecular geneticists working on Striga resistance. In addition, cultivars combining broad-spectrum resistance with good grain yields in Striga-infested fields can be recommended to rice farmers in Striga-prone areas.

Evaluation of rice and sweetcorn-based cropping system for rainfed upland ecosystem of Eastern India

In the eastern India, rainfed area occupies nearly two-third of its total cultivable area. Rice is the predominant crop which is no more beneficial to farmers of the region due to its low yield. So there is a need to change in a cropping system and to find better crop substitution which can give more returns to the farmers than the existing system. With this view, the study was conducted at Indian Institute of Technology Kharagpur to evaluate rice and sweetcorn based cropping system for rainfed upland ecosystem of Eastern India. For this purpose two cropping systems, rice-peanut and sweetcorn-peanut were taken into consideration. Two crop growth simulation models viz., CERES-rice and CERES-maize of DSSAT v4.0 (Decision Support System for Agrotechnology Transfer) were used to simulate the rice and maize yield of the region using historical weather data at Indian Institute of Technology Kharagpur for the years 1978 to 2007. The field experiment was carried out and the experimental data of yield components (yield and top weight) for the years 2009 to 2011 were used to calibrate and validate both the models. The comparative assessment of economic feasibility of the cropping systems (rice-peanut and sweetcorn-peanut) was also carried out to identify suitable cropping system for the region. The results of the models validated statistically which revealed that the models can predict the yield components with high accuracy. The net income from 1 hectare for rice-peanut and sweetcorn-peanut cropping pattern was Rs. 64415 and Rs. 90330, respectively. So it was concluded from the study that, for the rainfed upland ecosystem of Eastern India, sweetcorn- peanut cropping system was more beneficial than rice-peanut cropping system. Sweetcorn-peanut cropping system can be adopted for the sustainable development in the region.

Rainwater harvesting options for rice–maize cropping system in rainfed uplands through root-zone water balance simulation

A root-zone water balance model was used to simulate the soil moisture storage of maize (Zea mays L.) and rice (Oryza sativa L.) fields in rainfed uplands of eastern India. The simulation study revealed that short duration (95 days) rice fields in uplands remained under ponding condition for a period of 32 days during the entire growing season. Based on the ponding depth requirement in rice fields (50 mm), excess ponding was found for seven days only out of the 32 days of ponding. In contrast, the maize field under similar length of growing season (95 days) and topographic condition could produce harvestable runoff for 23 days. Furthermore, the rice crop was to remain under moisture stress for eight days during its mid-season stage, whereas the maize was found to be without stress during entire growing season. Before sowing of winter crops, the soil moisture in the seeding zone was determined to be depleted below germination soil moisture for 18 and 19 years out of 30 years of simulation in rice and maize fields, respectively. This implies that a second crop, following withdrawal of monsoon, is not possible without pre-sowing irrigation in three out of five years in rainfed uplands. Thus, complete substitution of rice by maize in uplands would create a better scope for rainwater harvesting. Alternatively, partial replacement of rice could be a viable option for meeting both rice demand of the people and harvesting of adequate rainwater for supplemental irrigation to crops in rainy and winter seasons.

Assessment of unterraced and terraced farming system on livestock development in mid-hills of Nepal

The unterraced farming (Pata) system which is being practiced in few districts of mid hills of Nepal was assessed in terms of livestock holding and livestock feed availability against the terraced farming system. Field study and household survey was conducted in Arghakhanchi (representing unterraced/Pata) and Tanahun (representing terraced) farming system by selecting 90 households (HHs) from each districts randomly. The study showed that there was only 1.89 Livestock Unit (LU)/HH in Arghakhanchi as compared to 2.64 LU/HH in Tanahun (p<0.01). Dry matter (DM) output per hectare rainfed upland in Tanahun was 6.09 Metric Ton (MT) whereas it was only 3.82 MT in Arghakhanchi (p<0.01). The farming system of Arghakhanchi has created livestock feed shortage, consequently has compelled farmers to raise least number of animals. Hence unterraced farming system of Arghakhanchi needs correction for better livelihood of people as well as improvement in environmental condition.

Economics and yield performance of some short duration fruit and medicinal crops under agrisilvicultural system in rainfed uplands of Odisha

A field experiment was conducted during 2011-12 in an agrisilvicultural system consisting of two silvicultural species viz. Acacia mangium (mangium) and Gmelina arborea (gamhar) planted in 2000 at a spacing of 8m x 2m and four agricultural crops viz. Ananas comosus (pineapple), Aloe vera (aloevera), Andrographis paniculata(kalmegh) and Curcuma amada (mangoginger) were raised in the 1st week of July, 2011.The maximum volume increment were achieved by mangium with pineapple (16.53 m3/ha). Pineapple also registered the maximum fruit yield of 9981Kgha-1 under mangium and minimum under gamhar (9106 Kgha-1). The fresh leave yield of aloevera (8635Kg ha-1) was maximum under mangium which is statistically at par with gamhar. However, kalmegh recorded maximum dry plant yield of 1239 Kgha-1 under open condition followed by 1072 Kgha-1 under gamhar and 823 Kgha-1 under mangium. Similarly, mangoginger exhibited maximum rhizome yield of 3300 Kgha-1 under open condition followed by 1979 Kgha-1 under gamhar and 1597 Kgha-1 under mangium. The trend of crop yield under both the trees and open condition was: Pineapple >Aloevera>Mangoginger>Kalmegh. A. mangium with pineapple based agrisilvicultural system recorded the highest gross return, net return and BCR as compared to other agrisilvicultural systems and sole crops.

Genetic variability among traits associated with grain yield of rice (Oryza sativa L.) exposed to drought at flowering stage

Morphometric and biochemical characterization of eighteen rainfed upland rice genotypes were studied under drought stress situation. Relation of the studied traits was also observed with grain yield under drought stress situation. A significant variation among the rice genotypes were observed and a significant genotype × environment interaction for all the traits was seen indicating better scope for drought tolerance and improvement in yield. The different biochemical parameter that is, shoot starch at maturity, leaf’s starch, upper root’s and lower root’s carbohydrate under both the conditions were positively increased. However, proline in irrigated condition was the only trait which possessed very high estimates of phenotypic and genotypic coefficient of variation, heritability (h2b) and genetic advance (Ga). Traits like, chlorophyll a, nitrate reductase activity, carbohydrate at flowering, starch at maturity, leaf’s carbohydrate, leaf’s starch and lower root’s starch showed positively high (desired) genotypic correlation as well as direct effect on grain yield. SDS-PAGE profiling in control and drought condition was conducted and 25 kDa proteins was found to be induced in resistance rice genotypes. Drought tolerance of well-known cultivars- Vandana, NDR-359, Azucena, Moroberekan, P-0326 and TN-1 (DSI 75%) was validated through biochemical as well as physiological characterization in the study. These traits showed a promise for selection parameters for the drought stress situation. Key words: Correlation, drought susceptibility index, drought tolerance efficiency, path coefficient, genetic advance, upland rice and variance.

Integrated Nutrient-Management Technology for Direct-Seeded Upland Rice (Oryza sativa) in Northwestern Himalayas

Alarming climate change, rainfed upland farming, and low resource-use efficiency of conventional fertilizer management practices are major production constraints detrimental to rice productivity in the northwestern (NW) Himalayas. Recent agronomic intervention of direct-seeded rice (DSR) coupled with suitable rice germplasm well suited to rainfed upland ecosystems in combination with appropriate integrated nutrient-management (INM) technology can enhance the rice productivity in the region. Thus, a field experiment with seven treatments replicated three times in a randomized block design was conducted on INM technology in rainfed upland rice cv. HPR-1156 (Sukaradhan-1) to harness the potential of DSR technology in order to boost rice productivity in the NW Himalayas. Results on INM in direct-seeded upland rice revealed that nitrogen, phosphorus, and potassium (NPK) at 90:45:45 kg ha−1 + farm yard manure (FYM) at 5 t ha−1 (oven dry-weight basis) significantly resulted in the greatest magnitude of growth and development (plant height, tillers m−2) and yield-contributing characters (panicles m−2, panicle length, grains panicle−1 and 1000-grain weight), resulting in significantly greatest grain, straw, and biological yield followed by sole use of NPK at 90:45:45 kg ha−1 and NPK at 60:30:30 kg ha−1 + FYM at 5 t ha−1, respectively, in rainfed upland rice. Application of NPK at 90:45:45 kg ha−1 + FYM at 5 t ha−1 again resulted in significant improvement in soil organic carbon and available NPK status over other treatments and initial soil fertility status in an acidic Alfisol. Overall, it is inferred that INM technology with judicious use of NPK at 90:45:45 kg ha−1 + FYM at 5 t ha−1 in rainfed upland rice under DSR technology can enhance the rice productivity and resource-use efficiency in NW Himalayas.

Effect of QTLs controlling grain yield under drought stress in the genetic background of ADT45 rice variety

Drought is a major production constraint in rain-fed upland and rainfed lowland ecosystems of rice cultivation. A set of two backcross inbred lines (BILs) harboring mega effect QTLs controlling grain yield under stress were developed in the genetic background of ADT 45 through marker assisted selection (MAS) and evaluated for drought tolerance at reproductive stage under rain out shelter. Background selection of BILs showed highest recovery (90%) of recipient genome in the BIL harboring three major QTLs from Apo a tolerant donor. Significant differences were observed among the BILs and parents for grain yield and its contributing traits under both severe moisture stress and well irrigated conditions when compared to ADT 45. The BIL harboring three major QTLs, DTY (2.2+3.1+8.1) [QTLs for yield under stress on chromosome 2,3 and 8] performed better and showed increased values for grain yield, plot yield, spikelet fertility and harvest index than the BIL harboring 2 major QTLs DTY (3.1+8.1), which shows pyramiding of more number of QTLs may enhance the grain yield under stress. Both the BILs harboring two and three major QTLs recorded lesser Drought Susceptible Index under severe moisture stress.