Yield Of Rice Genotypes Research Articles

Performance of different rice genotypes cultivated under submergence and normal growing conditions

Abstract Submergence negatively affects the plant growth and yield of rice genotypes, which in turn results in huge financial loss. Thus, identification of submergence tolerance rice genotypes is needed for sustainable rice cultivation in flood-prone areas. Keeping this in view, a two-year (2019 and 2020) field study was undertaken at Rice Research Farm of Bihar Agricultural College, Bihar Agricultural University, Sabour, Bhagalpur to investigate and compare the yield responses of rice genotypes under submergence and normal growing conditions. Twenty-five days old seedlings of 25 rice genotypes were transplanted in a randomized complete block design in two replicates, which were allowed to grow under normal practice for the next 25 days. Thereafter, the 50-day old plants were completely submerged with turbid water of 1.5 m height for the next 18 days. After de-submergence, all the recommended agronomic practices were adopted during the rest of the crop period. Under submergence, higher grain yield was recorded under all the genotypes during 2020 as compared to 2019 mainly due to higher temperature and lesser rainfall during 2020. Under submergence conditions, Jalmagna, Nona Bokra and Swarna Sub 1 were the best performers having produced average yields of 3,167, 2,786 and 2,741 kg/ha, respectively. Whereas under normal growing practice, Swarna Sub 1, Jalmagna and Sudha were the first three best performing genotypes producing average yields of 5,063, 4,565 and 4,456 kg/ha, respectively. Therefore, Jalmagna should be preferred for cultivation in the flood-prone regions of the state, however in non-flooded areas; Swarna Sub 1 may be cultivated.

The Nutrient Content, Growth, Yield, and Yield Attribute Traits of Rice (Oryza sativa L.) Genotypes as Influenced by Organic Fertilizer in Malaysia

One of the most important challenges to continuously maximizing crop production on limited areas of agricultural land is maintaining or enhancing soil fertility. Organic fertilizer application is needed to replace nutrients recovered by crops from the fields in order to restore the crop production potential of the soil. The utilization of chicken manure as an organic fertilizer is essential in improving soil productivity and cop production. In Malaysia, demand for rice as a food source is rising in tandem with population growth, while paddy rice production capacity is becoming increasingly constrained. Field experiments were carried out in Sungai besar, Kuala Selangor, Malaysia during the two planting seasons in 2020 to evaluate the effects of different levels of organic fertilizer on the growth and yield of rice genotypes. A split plot layout in a randomized complete block design with three replicates was used. The twelve rice genotypes were in the main plots. The sub-plots were treatments. The experiment comprised 4 treatments, viz., T1 = 100% NPK (N150P60K60), T2 = Chicken manure @ 5 t ha−1, T3 = Chicken manure @ 7 t ha−1, and T4 = Chicken manure @ 10 t ha−1. The study indicated that different levels of chicken manure and NPK fertilizer showed significant effects on growth, yield, and yield contributing characters of all the rice genotypes. Results showed that application of chicken manure 10 t ha-1 was the best in producing growth and yield contributing characters, grain and straw yields, and also nutrient (N, P, and K) contents in grain and straw. The maximum number of panicles (422.56 panicles m−1), the maximum number of filled grains (224.49 grains panicle−1), and the maximum grain yield (8.02 t ha−1) and straw yield (9.88 t ha−1) were recorded from T4 treatment at the rice genotype BRRI dhan75. Although the highest biological yield was recorded from T4 treatment, a statistically similar result was found for T3 treatment. The highest harvest index was also recorded for T4 treatment. Therefore, rice genotype BRRI dhan75 can be recommended under chicken manure @ 10 t ha−1 for rice production in Malaysia.

Effect of Organic and Inorganic Fertilizer on the Growth and Yield Components of Traditional and Improved Rice (Oryza sativa L.) Genotypes in Malaysia

Rice is the most important staple cereal human nutrition and consumed by 75% of the global population. Rice plants need a supply of essential nutrients for their optimal growth. Rice production has increased tremendously in Malaysia insensitive irrigation and the use of inorganic fertilizers and pesticides. However, the effect of using inorganic fertilizers resulted in contamination of ground water and decreased the productivity of soil, which in turn affected the rice production in the long term. The use of organic manure may help to regain the soil health, but that is insufficient for providing the essential nutrients to achieve optimal growth. Therefore, the use of organic manure combined with inorganic fertilizers is applied to obtain optimum yields. This study aims to test the effect of organic and inorganic fertilizers on the growth and yield components of 65 rice genotypes. The pot experiment was conducted at the net house on field 10, University Putra Malaysia, UPM, Malaysia, during the period of February to June 2019 and August to December 2019 in a randomized complete block design (RCBD) with three replications. There were three treatment combinations viz. T1: 5 t ha−1 chicken manure (CM), T2: 2.5 t ha−1 CM + 50% CFRR, T3: 100% (150 N: 60 P2O5: 60 K2O kg ha−1) and chemical fertilizer recommended rate (CFRR). Grain and straw samples were collected for chemical analysis, and physical parameters were measured at the harvest stage. Results showed that most of the growth and yield components were significantly influenced due to the application of organic manure with chemical fertilizer. The application of chemical fertilizer alone or in combination with organic manure resulted in a significant increase in growth, yield component traits, and nutrient content (N, P, and K) of all rice genotypes. Treatment of 2.5 t ha−1 CM + 50% CFRR as well as 100% CFRR showed a better performance than the other treatments. It was observed that the yield of rice genotypes can be increased substantially with the judicious application of organic manure with chemical fertilizer. The benefits of the mixed fertilization (organic + inorganic) were not only the crop yields but also the promotion of soil health, the reduction of chemical fertilizer input, etc.

Growth and Productivity Assessment of Short-Duration Rice (Oryza sativa L. and Upland NERICA) Genotypes in Semiarid North-Central Namibia

In semiarid regions, drought is the major threat to crop production, but climate change and variability often bring floods to the regions, forming seasonal wetlands causing damage to local, drought-adapted staple grains and, hence, low yields and food deficit. Introduction of the semiaquatic crop rice (Oryza spp.) to these semiarid wetlands could complement the dryland crop low yields and overcome the food shortage problem. A field experiment was carried out at the University of Namibia-Ogongo Campus during the 2016/2017 and 2017/2018 cropping seasons to assess the growth and yield of rice genotypes. Twelve short-duration rice genotypes, nine from the International Rice Research Institute (IRRI) and three locally grown upland NERICA genotypes, were used. Parametric analysis of variance was performed to test their effects on crop growth and yield characters. The results showed significant genotype by year interaction for days to heading, plant height, the number of tillers per m2, shoot biomass, the number of panicles per m2, 1000-grain weight, harvest index, and grain yield. The IRRI genotypes produced a higher number of tillers, shoot biomass, and grain yield than the NERICA ones, which were early maturing, were taller, and had higher 1000-grain weight across the years. Generally, most of the genotypes had lower grain yield and higher shoot biomass in the first year, due to the prevailing cool, rainy, and seemingly cloudy weather conditions associated with lower temperature and lower solar radiation. Grain yield was positively correlated with most characters but negatively correlated with the 1000-grain weight. These results demonstrate the yield superiority of IRRI genotypes over their early-maturing NERICA counterparts. However, further studies on morphological characters and drought tolerance of the IRRI genotypes are warranted to ascertain production sustainability under semiarid environments.

Impact of High Temperature Stress on Morpho Physiological Traits and Yield of Rice (Oryza sativa L.) Genotypes

High temperature stress is a major environmental factor that affects crop growth, development and yield, it especially limits rice yield. Hence, an experiment was conducted to study the impact of high temperature on morpho-physiological parameters and yield of rice genotypes. Ten rice genotypes were used in this study viz., N22, ADT 36, ADT 37, ADT 43, ADT 45, CO 51, ASD 16, MDU 6, TPS 5 and Anna (R) 4. The study was carried out at OTC (Open Top Chamber) with the treatments of ambient, ambient +2O C and ambient +4O C. Stress was imposed from anthesis to early grain filling period. Observations on plant height, the number of tillers, leaf area, SPAD (Chlorophyll index) and chlorophyll stability index (CSI) were done after the stress imposement and grain yield was calculated after harvest. Results revealed that, the significant changes were observed in morpho-physiological traits and grain yield of rice genotypes among the treatments and with the genotypes. N22 (10% and 19%) and Anna (R) 4 (12% and 22%) recorded less reduction of grain yield in ambient +2O C and ambient +4O C compared with ambient, due to less reduction of total chlorophyll content, SPAD values, leaf area and increased plant height. These parameters resulted in higher biomass which indirectly contributed to higher grain yield in N22 and Anna (R) 4 under high temperature

Simulating the Production of Rice Genotypes by Flood Management and End-Season Water Stress Conditions Using AquaCrop Model

ABSTRACT The present study was conducted to assess the ability of AquaCrop model in predicting of grain and biological yield of rice genotypes in water management. A two-year field experiment was conducted at the experimental farm of the Iranian Rice Research Institute in Rasht, Iran from 2016 to 2017. The experiment was established in a split-plot design with two irrigation management (continuous submergence and end season water stress) as the main plot, fourth rice genotypes as the sub-plot and three replications. The goodness-of-fit between observed and simulated grain yield and final biomass was assessed by means of the coefficient of determination (R 2), the absolute and normalized root mean square errors (RMSE). The RMSEn of predicting grain yield at calibration and evaluation stages was in the range of 6–12% and 6–8% for biological yield. The results indicated that AquaCrop model is suitable to predict grain yield and biological yield of rice genotypes in northern Iran. AquaCrop model can be used to determine optimization strategies to improve the water consumption of rice genotypes.

Effect of weed species on drought tolerant rice genotypes at Sundarbazar, Lamjung, Nepal

Abstract Weeds compete with rice for water, nutrients, space and light. The effect of weeds on productivity of rice genotypes were studied at research field of Institute of Agriculture and Animal Science, Lamjung Campus, Lamjung, Nepal in 2016. Eight rice genotypes (IR-87684- 18-1-2-3, IR-83388-3-3-140-4, IR-8839-39-1-6-4, IR-87759-7- 1-2-3, IR-88966-22-1-1-1, IR-88839-3-1-2-2, IR-88869-2-2-2-2, and Sukhadhan-3) and two weed management practices (Weeded condition and non weeded condition) were studied in randomized complete block design (RCBD) with three replications. Results showed that weeding operation significantly increased the growth traits and final yield of rice genotypes. Non-significant results among tested genotypes were obtained for grain yield and straw yield however the maximum grain yield (3.68 t ha-1) and straw yield (5.99 t ha-1) were found in IR-88839- 39-1-6-4 which might be due to highest test grain weight (30.64 g), tallest plant height (105.7m) and lower sterility percentage (21.84%). Similarly, the relative grain yield loss due to weed infestation was 41.8%. The highest grain yield (3.99 t ha-1) and straw yield (6.90 t ha-1) was found in weeded plots compared to non-weeded plots (2.321 t ha-1 and 6.43 t ha-1, respectively). Among weed species, Rotala indica was found most dominant (1091 m-2) and proportion 18%) followed by Eriocaulon cinereum (245.83 m-2 and 12%). Interaction effect between variety and weed population showed non-significant results for all growth and yield attributes. The plots having highest number of weed population showed greater loss of rice yield. Thus this study suggests that weeding should be carried out to achieve higher rice production.

Enriching Rice Grain Zinc through Zinc Fertilization and Water Management

Core Ideas Rice grain‐Zn concentration increased with more aerobic soil conditions. Fertilizer‐Zn applied to soil had limited effect on rice grain‐Zn concentration. Rice paddy water management affected soil redox potential and DTPA‐extractable Zn. Combined water and Zn management are useful for agronomic Zn biofortification. Agronomic biofortification was not sufficient to meet rice Zn nutrition targets. Increasing rice (Oryza sativa) grain‐Zn concentration is important for achieving improved human nutrition. Our objective was to understand how agronomic management practices, including water management and fertilizer‐Zn application rate and timing, affect plant growth, grain‐Zn concentration, and yield of rice genotypes. In a series of four‐field experiments over three seasons, we tested multiple combinations of water management techniques and fertilizer‐Zn application techniques. The use of alternate wetting and drying (AWD) water management increased (p < 0.001) soil redox potential and diethylene triamine pentaacetic acid (DTPA)‐extractable soil Zn compared with continuous flooding (CF) in the 0‐ to 2‐cm soil depth, but not always in the 2‐ to 10‐cm depth. On average, AWD grain‐Zn concentration increased 9% over CF without any yield penalty. Fertilizer‐Zn application increased DTPA‐extractable Zn only in the top soil layer and only temporarily, with a corresponding increase in grain‐Zn concentration only at rates > 10 kg Zn ha−1. Different timings of fertilizer‐Zn application (from basal to flowering) had no effect on grain‐Zn concentration or yield. Overall, our results indicated that AWD had a consistent and larger positive effect than fertilizer‐Zn application on grain‐Zn concentration. However, the increase in grain‐Zn concentration due to fertilizer‐Zn or water management was small, up to 2 mg Zn kg−1 brown rice, implying that improved agronomic management alone is not sufficient to meet the target increase of at least 10 mg Zn kg−1, but is a useful complementary strategy for enhancing the performance of Zn‐enriched rice by improving soil‐Zn availability.

Relation between agrometeorological indices, crop phenology and yield of rice genotypes as influenced by real time N management

Field experiment was conducted during 2012 and 2013 to study yield variations in rice genotypes (Oryza sativa L.) due to leaf colour chart (LCC) based N application and agrometeorological indices. Treatments included two rice genotypes (Jhelum and SR-2) and eight rates of N application (control, recommended practice (120 kg N ha-1) and LCC d” 3, 4 and 5 @ 20 and 30 kg N ha-1) laid out in randomized block design replicated three. The pooled data showed that SR-2 recorded significantly higher value of yield and growing degree days (GDD), heliothermal units (HTU) and heat use efficiency (HUE), besides took more days to reach different phenophases as compared to Jhelum. LCC d”5 @ 30 and 20 kg N ha-1 recorded significantly higher grain yield, GDD, HTU, HUE and took maximum number of days to different phenophases. This indicated that N application based on LCC 5 should be adopted in rice cultivars particularly SR-2 to achieve maximum yield under temperate conditions of Kashmir valley.

Simulation of genotype performances across a larger number of environments for rice breeding using ORYZA2000

Breeding line selection with conventional field methods is limited by time, cost, and appropriate environments. Crop models can be used as a tool to assist in breeding line selection by extrapolating the results of multiple-environment trials (MET) to large environments in a cost-effective and faster manner. This study is the first attempt to use ORYZA2000 for the selection of drought-resistant rice genotypes, and it provides a ‘virtual’ platform for a large number of environmental trials. In a case study, ORYZA2000 results from two field experiments in two environments were extrapolated to 669 environments in South Asia. For these two field experiments, the differences between simulated and field-measured grain yield and total above-ground biomass for all the 69 genotypes were within the standard deviations of the field measurements. This result confirmed that ORYZA2000 has the capability to correctly represent the growth and yield of rice genotypes under different environments. Using simulation outputs for 69 genotypes in 669 environments, the performance of these genotypes was evaluated for rainfed conditions with various drought stress. With the increase in the number of environments, the effect of the genotype on phenotypic performances across environments become much more significant than that of the effects of environment and genotype–environment interactions, and heritability was also increased. Desirable rice genotypes could then be selected by breeders based on the expected yield and adaptability to various environments generated by the model. The evaluation of rice genotypic performance by ORYZA2000, as ‘virtual’ multiple-environment trials, can improve the reliability of selected genotypes for a wide range of environments and enhance efficiency in terms of time consumption and cost effectiveness of the breeding process.

Effect of Salinity on Photosynthetic Efficiency and Yield of Rice Genotypes

Effect of Salinity on Photosynthetic Efficiency and Yield of Rice Genotypes

Silicon, Disease Resistance, and Yield of Rice Genotypes under Upland Cultural Conditions

Silicon deficiency limits rice (Oryza sativa L.) yield on highly weathered upland soils in West Africa and can increase susceptibility to some diseases. A study at Onne, Nigeria, examined responses of different genotypes to increasing Si supply under upland cultural conditions. Without applied Si, average shoot Si concentration was one‐fifth of the minimum recommended value for rice, confirming deficiency. Application of 18.7 g Si m−2 as sodium metasilicate doubled plant Si concentration and increased grain yield by 48%, and significantly reduced the severity of husk discoloration, neck blast, sheath blight, and leaf scald diseases. When grown in flooded paddies on the same soil at Onne, and on a more fertile Alfisol at Ibadan, mean leaf Si concentrations were two to three times greater than in Si‐treated upland plots, and diseases were negligible. Under upland cultivation, African japonica upland rice genotypes had 50 to 100% higher Si concentration in mature flag leaves, and were more resistant to husk discoloration and neck blast, than Asian indica upland genotypes. The japonicas were equally susceptible to leaf scald, however, and more susceptible to sheath blight than the indicas. It is concluded that increasing the supply of Si to the crop through flooding is the most effective method of ameliorating Si deficiency. Where this is not practical, genes for higher Si content can probably reduce losses to some diseases, but other genetic factors seem also to have major effects.