Improved Rice Varieties Research Articles

Breeding Rice to Increase Anthocyanin Yield Per Area through Small, Black Grain Size and Three Grains per Spikelet

Rice varieties with high anthocyanin content are often recognized for their vibrant colors and health benefits. The demand for rice with high anthocyanin is increasing domestically and internationally due to consumers becoming more health-conscious. However, the current increase in yield might not raise the anthocyanin content due to its location in the grain pericarp and seed coat, which are relative to the grain surface area. This study aims to develop rice lines to increase anthocyanin yield per production area by improving rice varieties with small, black, and three grains per spikelet. Accordingly, six rice recombinant inbred lines (RILs) were bred by crossing Niaw Dam Chaw Mai Pai 49 (NDCMP49) with Khao Nok (LLR059). The grain color, size, and number of grains per spikelet were selected from the F1 to the F4 population through the pedigree selection method. Six RILs and their parents were assigned in a randomized complete block design (RCBD) with three replications under field conditions during the rainy season of 2021 and 2022 in four locations. The results showed statistically significant differences in environmental conditions, affecting productivity and the yield components of rice lines. Consequently, the rice lines adapted to a specific environment, and there were significant differences in genotype. This study identified three RILs with higher yield performance (13-1 (3842 kg/ha), 374-1 (3699 kg/ha), and 903-3 (3550 kg/ha)) compared with the parent NDCMP49 (1996 kg/ha). However, the grain yields were unstable in the three top-yielding RILs due to varying environmental conditions, indicating that selective breeding requires a specific, narrow environment. Based on grain yield and grain size, the RILs performed better in the grain surface area than in the parent NDCMP49. Moreover, only two RILs (374-1 and 903-3) produced the highest anthocyanin content and yield, although this was lower than in the parent NDCMP49. However, the 374-1 and 903-3 RILs produced more grains, black grains, and three grains per spikelet with high yield and moderate anthocyanin content. They can, therefore, be backcrossed to the parent NDCMP49 to increase the accumulated anthocyanin content with a stable, high yield. This work provides a resource of small grains, black grains, and three grains per spikelet in the rice breeding line for breeding programs in the future.

Combining Ability, Heterosis and Potence Ratio for Yield and Yield Components in Korean Double-Haploid, Progenies and Improved Rice Varieties in Nigeria

Rice is the most widely consumed staple crop in Africa and consumption continues to grow at a rapid pace with increasing population. Success in breeding programs are largely dependent on the genetic diversity of a crop. Genetic variability occurs due to genetic differences in individuals within a given population, which is the basis of plant breeding. Thus, if the genetic variability is well managed, diversity can result to permanent gains in the performance of the crop. The objectives of this study were to determine the interaction between grain yield and yield components and to conduct genetic studies on selected rice genotypes. The research was carried out at the University of Port Harcourt Faculty of Agriculture teaching and research farm. Thirteen (13) varieties were used which comprised 7 adapted Nigerian varieties and 6 Korean rice varieties in a randomized complete block design (RCBD) in three replications was established. All agronomic practices were carried out at appropriately crop phenology. North Carolina II mating design was used to perform crosses. Data was collected on 10 agronomic traits. All means were subjected to ANOVA, combining ability, Heterosis and Potence ratio were determined. The progenies from UPIA 2 x UPN 234, FARO 52 X UPN 266 and UPIA 3 X UPN 266 had the best phenotypic and genotypic expression and most of the hybrids had heterotic values than their parents. The results also showed ranges of dominance for genotypes. UPIA 1, UPIA 2, UPN 223, UPN 234 and UPN266 should be included in breeding programs because they showed the best GCA’s across most traits.

Evaluating the effects of nitrogen application on the agricultural performance of improved rice varieties in Marin, Sindhuli, Nepal

This study focuses the agronomic performance of two rice varieties, Ram Dhan and Sabitri Dhan, under varying nitrogen levels in central inner terai Sindhuli, Nepal, conducted from June to October 2022. The primary motivation is to understand the nuanced impacts of nitrogen application on key physiological traits and yield components without assuming statistically significant differences. The central problem addressed is to explore how different nitrogen levels interact with these traits and influence overall crop productivity. Our study hypothesizes that nitrogen application may affect agronomic parameters such as flag leaf characteristics, culm dimensions, tiller number, flowering dynamics, panicle morphology, and grain yield. The experiment utilized a factorial randomized block design with six treatments and four replications, applying nitrogen levels (100 kg/ha, 120 kg/ha, 140 kg/ha) at split doses during critical growth stages. Data collection included meticulous measurement of these traits following standard agronomic protocols. Key findings revealed that while Sabitri Dhan tended to show higher tiller numbers and panicle traits compared to Ram Dhan, Ram Dhan exhibited marginally better grain yield and harvest index. These results suggest that despite the absence of statistically significant differences, there are practical implications for rice cultivation practices in similar agro-ecological contexts. The study underscores the importance of considering non-significant results in agricultural research to refine nutrient management strategies and enhance crop productivity sustainably. Future research could further explore the nuanced interactions between nitrogen levels and rice varieties to optimize agronomic practices tailored to local conditions and improve yield stability and resilience in rice cultivation.

Sustainability of Adoption of New Improved Rice Variety Innovation in West Kalimantan Coastal Areas: Review of Social and Cultural Aspects

As a staple food in Indonesia, rice has significant socio-economic value, especially in regions such as West Kalimantan. However, the variability of rice production poses a challenge to food security and economic stability. This study assesses the sustainability of the adoption of new improved rice varieties (VUBs) in West Kalimantan, focusing on social and cultural aspects using Multi-Aspect Sustainability Analysis (MSA). Focus group discussions and expert interviews were used to identify important factors affecting VUB adoption. The results indicated a sustainable adoption status (54.17%), with potential for improvement (58.33%) in the future. Farmer education emerged as the most sensitive factor, highlighting the need for educational interventions to improve technology access and adoption. In addition, farmers' knowledge of VUB, culture of mutual cooperation, the absence of social conflict, and positive consumer preference for VUB rice are also critical for adoption. Recommendations include targeted educational interventions, improved knowledge dissemination strategies, consideration of the cultural context, conflict management approaches, and market-oriented strategies to sustainably increase VUB adoption. Addressing these factors can contribute to sustainable agriculture and rural development in West Kalimantan and similar contexts, ensuring long-term benefits for farmers and food security.

Food security drive and adoption of improved rice varieties on the production efficiencies of upland and lowland rice farmers in north-central Nigeria

To attain the food security target of the country, fostering farmers’ adoption of improved rice varieties will go a long way toward closing the lingering production deficit gap in Nigeria, and meeting up with the ever-increasing demand for rice consumption in the country. This study investigated the effect of the adoption of improved rice varieties on the production efficiencies of rice farmers in the north-central Nigeria. A multistage sampling technique was uses to select 387 rice farmers, which includes 201 upland and 186 lowland rice farmers in the study area. A stochastic frontier analytical model (SFA) was employed to estimate production efficiencies (technical, economic and allocative) for the rice farmers. Further, a multivariate regression analysis (MVA) was applied to determine the effect of adoption on the efficiency levels of the rice farmers. The exploratory analysis of the data revealed that the rice varieties available for adoption by the rice farmers in the study area is 10, but both upland and lowland rice farmers adopted more of two rice varieties (Faro-46 and Faro-52). From the SFA results, most of the rice farmers have mean technical, economic and allocative efficiencies of 0.7, 0.54 and 0.76 respectively. The SFA estimates also indicated that seed, herbicide, fertilizer, farm size and capital assets significantly affect the efficiency of upland rice farmers, while the efficiency of their lowland counterparts is influenced by seed, farm size capital and herbicide, amongst others. The MVA estimates also showed that the adoption rate of improved rice varieties, years of formal education, and farm-level factors made significant contributions to the efficiency levels of the rice farmers. Importantly, the levels of adoption of all rice varieties by farmers indeed influenced their technical and economic efficiency, while having no impact on their allocative efficiency. The study recommended that the government, research institutes and developmental agencies should promote easy access to improved rice varieties by farmers, as this can further drive sustained adoption. This can evidently help to achieve desirable yield and enhance the efficiency level of the rice farmers and boost food availability and achieve the zero-hunger target in the study area and Nigeria at large.

The productivity and income effects of adopting improved rice varieties by smallholder farmers in Indonesia

PurposeThis study identified the determinants of improved rice variety adoption and measured their impact on farm productivity and the income of smallholder farmers in Indonesia.Design/methodology/approachWe used a multistage sampling procedure and data from household surveys in four districts in the Banten region of Indonesia. An endogenous switching regression (ESR) model was used to estimate the impact of adoption, and the propensity score matching (PSM) non-parametric method tested the strength of the ESR findings.FindingsThe farm productivity of adoption increased by 11.45% and the income of smallholder farmers increased by 12.10% when compared to that of traditional methods.Research limitations/implicationsThe positive and significant effects of improved rice variety adoption indicated that research programs that develop improved rice varieties can optimize the productivity and income of smallholder farmers.Originality/valueAdopting improved rice varieties increases the productivity and income of smallholder farmers, and the level of education, rice farming experience, access to extension workers, off-farm work, and mobile phone ownership have positive and significant effects on the adoption of improved rice varieties.

The Landscape of Presence/Absence Variations during the Improvement of Rice

Rice is one of the most important staple crops in the world; therefore, the improvement of rice holds great significance for enhancing agricultural production and addressing food security challenges. Although there have been numerous studies on the role of single-nucleotide polymorphisms (SNPs) in rice improvement with the development of next-generation sequencing technologies, research on the role of presence/absence variations (PAVs) in the improvement of rice is limited. In particular, there is a scarcity of studies exploring the traits and genes that may be affected by PAVs in rice. Here, we extracted PAVs utilizing resequencing data from 148 improved rice varieties distributed in Asia. We detected a total of 33,220 PAVs and found that the number of variations decreased gradually as the length of the PAVs increased. The number of PAVs was the highest on chromosome 1. Furthermore, we identified a 6 Mb hotspot region on chromosome 11 containing 1091 PAVs in which there were 29 genes related to defense responses. By conducting a genome-wide association study (GWAS) using PAV variation data and phenotypic data for five traits (flowering time, plant height, flag leaf length, flag leaf width, and panicle number) across all materials, we identified 186 significantly associated PAVs involving 20 cloned genes. A haplotype analysis and expression analysis of candidate genes revealed that important genes might be affected by PAVs, such as the flowering time gene OsSFL1 and the flag leaf width gene NAL1. Our work investigated the pattern in PAVs and explored important PAV key functional genes associated with agronomic traits. Consequently, these results provide potential and exploitable genetic resources for rice breeding.

Performance of some improved rice varieties under direct seeded rainfed upland condition of Nagaland

A field experiment entitled “Performances of some improved rice varieties under direct seeded rainfed upland condition of Nagaland” was conducted to study the growth and yield performance under rainfed condition of Nagaland, at the School of Agricultural Sciences, Medziphema, Nagaland University, during kharif season of 2022-23. The experiment was laid out in Randomized Block Design (RBD) with three replications. Treatments viz., Kopilee, Jyoti Prasad, Dikhow, Joya, Chilarai, Kolong, Disang, Bishnu prasad, Luit, Lachit, and Leikhumo were studied. All the tested varieties were found to be semi-dwarf and dwarf varieties developed by Assam Agricultural University except Lekhimo (Nagaland local). In terms of growth and yield attributes, there were significant variations among different rice varieties. Leikhumo recorded significantly higher plant height (115.27 cm) among the tested varieties with the lowest, recorded in Bishnu prasad (74.01 cm). Chilarai showed superior parameters in terms of number of green leaves plant-1 (8.17), plant population m-2 (158), number of panicles m-2 (130), number of filled grains panicle-1 (124.33), test weight (25.55 g) and harvest index (42.95%), with Disang being the lowest viz., number of green leaves (6.06), plant population (110), number of panicles m-2 (91), number of filled grains (70.33), test weight (19.36 g) and harvest index (28%). In terms of crop growth rate and relative growth rate, Leikhumo performed the best whereas Disang variety was found inferior amongst all the varieties. Panicle length was also found to be highest in Leikhumo (26.20 cm) and the lowest in Disang (19.46 cm). Maximum grain yield was recorded in Chilarai (34.37 q ha-1 ) followed by Joya (31.92 q ha-1 ) and Leikhumo (29.62 q ha-1 ).

Impact of Improved Rice Variety Adoption on Smallholder Farmers Rice Productivity and Gross Farm Income Enhancement in North Western Ethiopia

The research was assessed status of adopting improved rice technology as well as evaluate its impact on rice productivity and gross farm income in Ethiopia. The research showed the importance of adopting improved rice technologies using impact evaluating techniques such as propensity scoring matching (PSM). The research was used descriptive and econometric methods of data analysis to elaborate the respondents’ characteristics, farming practices, adoption status and to estimate its impact. The research used multistage sampling methods to select 180 smallholder rice producers. Amhara and Benshangul Gumuz region are the potential rice producers which targeted for this study. Zones, districts and kebles of these regions were selected random that can be represent the region as well as the rice producers in Ethiopia. The research revealed that 44.44% of the respondents were adopted improved rice technology and pawe_1 is the most frequently used by respondents. The econometric result revealed that treated groups were gained high rice output 3,019.70 quintal per hectare over the controlled groups 1,971.40 quintal per hectare as well as in terms of gross income treated groups were earned higher income which is 46,159.78 ETHB than the controlled groups which were earned 29,797.14 ETHB on average. This indicated that adopting improved rice technology was brought 34.72% and 35.45% of increment in rice productivity and gross income on smallholders’ rice producers respectively. Adopting of agricultural technologies are a means of improving the smallholder farmers crop production, productivities and income generated from that farm activities. Therefore, any governmental and non-governmental institution should be focused on the outreach of these agricultural technologies to end user over all part of the country.

Path coefficient analysis using traditional and improved rice genotypes for trait effect on grain yield  

Accessions of traditional rice play a crucial role in preserving the genetic diversity of commercial rice. They contain specific and useful traits that can help to improve the overall yield, which cannot be achieved by relying solely on improved rice varieties. This is because traditional rice accessions display a wide range of morphological characteristics that contribute to their unique yield determinants. Fifty traditional and forty-five improved rice genotypes were evaluated for thirteen agronomic traits (days to 50% flowering, plant height, number of tillers per plant, number of effective tillers per plant, number of leaves per plant, panicle length, flag leaf length, flag leaf width, number of grains per panicle, filled grain percentage, 100-grain weight at maturity, grain length, and grain width) to understand the yield determination of traditional and improved rice genotypes. Path analysis was carried out using IBM SPSS AMOS statistical software to understand the difference in the direct and indirect effect of the studied parameters. The direct effect of effective tillers per plant (β = 0.519), filled grain percentage (β = 0.496), and hundred-seed weight (β = 0.403) on grain yield was high in improved rice varieties. In traditional rice accessions, the direct effect of effective tillers per plant (β = 0.746) and filled grain percentage (β = 0.395) on grain yield was high, but there was no direct effect of hundred seed weight. Filled grains per panicle recorded a moderate effect in both traditional (β =0.246) and improved (β = 0.266) rice genotypes. None of the studied parameters directly and negatively affected the yield of improved rice varieties. Still, several traits (flag leaf length, days to 50% flowering, panicle length, seed length, and seed width) negatively affected the yield of traditional rice accessions. The contributions of yield determinants in traditional rice accessions deviated substantially from those observed in improved rice varieties, highlighting the critical role of plant architecture in determining the final yield. Fertile tiller number, filled grain percentage and grains per panicle are possible traits that can be used in direct selection criteria for improved and traditional rice genotypes for high yield.

Nutritive Compounds of Traditional Rainfed Rice (Oryza glaberrima) from Goh-Djiboua and Mountains Districts in Côte d’Ivoire

Aims: The biochemical composition of rainfed rice (Oryza glaberrima) consumed in Côte d'Ivoire has not yet been revealed, whereas rice is of the main staple foods for many people. This work investigates the main biochemical traits of numerous traditional rainfed rice varieties from Ivorian environment, namely in Gôh-Djiboua and Mountains Districts, for better valorization.
 Study Design: Study performed on traditional rainfed rice varieties collected from 450 farmers in both regional Districts mentioned above. Shelled rice perceived per variety, conditioned, and total final 5.4 kg of resulted rice considered, 200g per variety, for due laboratory investigation.
 Place and Duration of Study: Sampling between January and June 2017, full analysis by 2018 in Laboratory of Food Sciences, Felix Houphouët- Boigny University.
 Methodology: All rice samples conveyed to laboratory, then 100g taken per variety, oven-dried at 50 °C/72 h, ground in metallic grinder, sealed into polyethylene bags, and kept into desiccator till analyses. Investigations consisted in triplicate evaluation of moisture, carbohydrates (total glucides, starch, soluble carbohydrates, reducing carbohydrates), fats, proteins, caloric energy, fibres, and ash by rice sample.
 Results: Great variability (P<.001) recorded between rive samples for biochemical traits assessed. Thus, the variety Jbröko represents the most important source of glucides (84.19±0.37g/ 100 g) and caloric energy (322.17±0.37kcal/ 100 g) compared to the other varieties. Oppositely, the variety Yoroukouiagnêzê recorded the highest proteins content (7.27±0.03 g/100g), whereas Abê provides more food fibres (6.67±0.14g/ 100g). Otherwise, the variety Danané belating is richer in free soluble sugars (4.63±0.08 g/100 g), while Azi red displayed more moisture content (10.96±0.1%) and Gbêklêazi is richer in lipids with content of 1.26±0.21g/ 100g. The top ash and starch contents were respectively recovered from varieties Zonhonkloumin black (1.38±0.02 g/100 g) and Abê (71.99±0.03g/ 100g).
 Conclusion: The studied rainfed rice record good nutritive traits above the widespread improved rice varieties. They remain significant caloric food resources thanks to considerable contents in glucides (varieties Abê, Akita, Jbröko, No-No-No, and Danané I), proteins, lipids, and significant amount of food fibre (varieties Boumabou, Glawlon, Dikouè, Loêgnini, and Danané fowl) and minerals. This nutritive composition could permit their quite usages for consumers and researchers, even though other investigations on the functional nutritional compounds should be performed.

Effect of Gamma Irradiation on Embryogenic Calli of Rice and Subsequent Shoot and Regeneration

This study was carried out during May 2021 to January 2022 at the Tissue Culture Laboratory of Biotechnology Division, Bangladesh Institute of Nuclear Agriculture (BINA), Mymensingh, Bangladesh for callus induction and regeneration ability of plantlet from low doses irradiated embryogenic calli of Binadhan-13 and BR5 (Dulabhog). The effect of low gamma rays such as 4, 6 and 8 Gy were observed in vitro shoot, root and plantlet formation. Two different incubation conditions such as light and dark incubation were maintained. Between two varieties, Binadhan-13 showed the highest ability of callus induction in both conditions. Callus induction was significantly higher under dark condition (77.14%) than light condition (67.14%) ‍at 21 days. Data revealed that gamma rays affect both shoot and root regeneration ability of embryogenic callus. Shoot regeneration ability was the highest at 4 Gy in Binadhan-13 (60%) and gradually decreased with the increased doses of gamma rays. Among the treatments, shoot regeneration ability (60% in Binadhan-13 and 50% in BR5) was higher at 4 Gy dose of gamma ray followed by 6 Gy where shoot regeneration ability was 55% and 45% in Binadhan-13 and BR5 respectively. In root induction, the highest root induction ability (80%) was observed in the cultivar Binadhan-13 at control condition. Like shoot regeneration, 4 Gy gamma ray showed better root induction in both the varieties (70% in Binadhan-13, 60% in BR5). The in vitro regenerated plantlets from irradiated embryogenic calli were successfully transferred to soil in pots. The regeneration protocol could be further used for varietal improvement of rice varieties using nuclear technique (60Co gamma ray). Bangladesh J. Nuclear Agric, 37(2): 29-42, 2023

Saturated, monounsaturated and polyunsaturated fatty acid profiles of commercially important traditional and new improved red and white rice varieties of Sri Lanka

The present study evaluated saturated, monounsaturated, and polyunsaturated fatty acid (FA) profiles of seven new improved and three traditional red and white rice varieties (RV) of Sri Lanka. Oil was extracted from whole grain rice flour, derivatized to methyl esters, and analyzed by gas chromatography (n = 3 each). Results showed significant differences (p < 0.05) in FA profiles among the RV, red vs white RV, and traditional vs new improved RV. The oil % of RV varied from 1.94–3.19%. Total FAs, saturated fatty acids (SFAs), monounsaturated fatty acids (MUFAs), polyunsaturated fatty acids (PUFAs), total unsaturated FAs, and PUFAs to SFAs ratios of studied RV varied from 19.40–31.90, 4.40–7.04, 8.35–13.60, 6.65–11.26 and 15.00–24.86 mg/g of rice and 1.44–1.83 respectively. The tested RV had four omega-6 FAs while omega-3 FAs were absent. The major FAs found in all RV were palmitic, oleic, and linoleic acids and these three FAs together contributed to 88–95% of the total FAs present in rice. Among these FAs, 70–76% were unsaturated FAs. Considering all, RV consisting of healthy fatty acid profiles could be identified by studying their total fatty acid profile rather than studying their oil % and the total fatty acid contents.

Hybrid Rice Production: A Worldwide Review of Floral Traits and Breeding Technology, with Special Emphasis on China.

Rice is an important diet source for the majority of the world's population, and meeting the growing need for rice requires significant improvements at the production level. Hybrid rice production has been a significant breakthrough in this regard, and the floral traits play a major role in the development of hybrid rice. In grass species, rice has structural units called florets and spikelets and contains different floret organs such as lemma, palea, style length, anther, and stigma exsertion. These floral organs are crucial in enhancing rice production and uplifting rice cultivation at a broader level. Recent advances in breeding techniques also provide knowledge about different floral organs and how they can be improved by using biotechnological techniques for better production of rice. The rice flower holds immense significance and is the primary focal point for researchers working on rice molecular biology. Furthermore, the unique genetics of rice play a significant role in maintaining its floral structure. However, to improve rice varieties further, we need to identify the genomic regions through mapping of QTLs (quantitative trait loci) or by using GWAS (genome-wide association studies) and their validation should be performed by developing user-friendly molecular markers, such as Kompetitive allele-specific PCR (KASP). This review outlines the role of different floral traits and the benefits of using modern biotechnological approaches to improve hybrid rice production. It focuses on how floral traits are interrelated and their possible contribution to hybrid rice production to satisfy future rice demand. We discuss the significance of different floral traits, techniques, and breeding approaches in hybrid rice production. We provide a historical perspective of hybrid rice production and its current status and outline the challenges and opportunities in this field.

Cost and returns analysis of upland and lowland rice production among farmers in North Central Nigeria

Sustainability of the rice production and farmers’ income in Nigeria raises a serious concern due to the rising costs of production inputs and other factors beyond farmers’ control. As a result, the study compared the cost and returns of rice production in North central, Nigeria. A multistage sampling technique was used to select 387 rice farmers in the study area. Descriptive statistics, gross margin analysis and seeming unrelated regression were used to analyze the dataset collected. The findings revealed that most of the rice farmers were male, averagely young and have at least 9 family members in their respectively households. Results from Kwara State showed that total cost is higher among the upland rice farmers compared to their lowland counterparts, but reverse was the case in term of net profit, as this favoured the lowland rice farmers. For Niger State and pooled data, the lowland rice farmers had higher net profit than the upland rice farmers. Seemingly unrelated regression estimates indicated that costs associated with fertilizer, herbicide, seed, pesticide and labour used were significant and influencing factors affecting the revenue of rice farmers in the study area. While inaccessibility to cheap farm inputs was the major constraint affecting the rice farmers, other challenges include lack of storage, inadequate rainfall and inadequate credit facilities. The study recommended seamless access to improved rice varieties by the farmers as this can scale up adoption of improved technologies, boost production and ultimately the net revenue of rice farmers. Farmers are also advised to join and/or form a registered occupational groups through which credit facilities can easily be accessed, to expand the farming operations because of the positive and complementary role of social group and access to credit.

Data-driven review on gender and rice varietal trait preferences in Bangladesh

In Bangladesh, farmers adapt to changing conditions through the adoption of improved varieties containing new or combined traits. The diverse varietal adoption decisions among farmers stem from gender-based differences in trait preferences. This review synthesizes existing knowledge to assess the nature, extent, and causes of gendered disparities in rice varietal trait preferences among farmers and consumers in Bangladesh. To enhance the data-driven nature of this review, we not only scrutinized secondary articles (45 documents) and databases but also incorporated and analyzed primary data on varietal adoption and trait preferences. The analysis revealed a pronounced need for rice breeding programs in Bangladesh to integrate both market and climate-smart traits, aligning with gender-specific needs in developing optimal rice product profiles. Analysis of primary data unveiled substantial variations in women and men farmers’ varietal trait preferences, influenced by factors like income, access to farming information, household size, land size, and decision-making. Consequently, addressing gender-differentiated trait preferences in the development of improved rice varieties is crucial to curtail farmers’ varietal adoption lag in Bangladesh. The findings underscore the necessity of systematic identification and integration of gender-differentiated varietal trait preferences into rice breeding programs. Failure to account for such preferences may disadvantage the gender-responsiveness of developed varieties and limit the anticipated impact. Therefore, understanding the biophysical, social, and cultural dynamics of diverse farmer groups from a gender perspective is imperative for achieving gender-responsive rice variety development in the context of Bangladesh. This process involves identifying key gender concerns for integration into rice breeding programs, ensuring a comprehensive approach to sustainable agriculture.

CLIMATE-SMART RICE PRODUCTION: A REVIEW

‌Rice is one of the world's most important crops and the primary source of nutrition for the world's more than half population. Currently, the world rice production is 495.78 million tons, while it will increase to 525 tons in 2050, which is not sufficient for the world's increasing population. At the same time, various climatic factors affect rice production, such as air temperature, atmospheric CO2, light, water, and soil nutrients. For instance, high temperature was the main climate factor that caused yield variation by affecting the rice maturity periods, spikelet fertility, and spikelet number. Thus, it is an urgent need to improve rice production and reduce the negative effects of climate change on rice production. In order to solve above-mentioned problem, one of the most important options is using climate-smart practices, which are planting improved rice varieties, soil and water conservation techniques, and adjusting planting and harvesting dates. The importance of adapting climate smart practices is an increase in rice yield by 15.87%. Climate-smart rice production and climate-smart practices in rice needs still to be investigated widely. The review objective is to describe climate-smart practices in rice cultivation, in order to mitigate the negative effects of climate change on rice production.

Channels and Methods of Communicating Agricultural Innovations to rice farmers in the Northern Region of Ghana

Rice Farmers in Ghana have benefited from technology dissemination programmes of high-yielding crop varieties to enhance their productivity and increase their incomes. The interventions in the rice sector of Ghana have led to a reduction in poverty, and reduced rice importation into the country. Despite the expected gains from the numerous interventions, there are low levels of adoption of improved rice varieties among many farmers in Ghana, partly due to ineffectiveness of the technology dissemination methods. This study examines rice farmers’ perception of the agricultural innovation communication channels and methods used to promote improved rice varieties in northern Ghana. Primary data was randomly collected (through survey, focus group discussions and key informant interviews) from 404 rice farmers and analyzed by percentages, means, standard deviations and explanations. The farmers perceived the innovation communication channels and methods that mostly helped them to adopt improved rice varieties as the effective ones. The empirical results show that fellow farmers, researchers and extension agents, and radio were perceived to be the most effective channels of innovation communication among the rice farmers. Farm and home visits, and demonstration farms, and radio broadcasts were also considered to be the most effective innovation dissemination methods used to promote improved rice varieties in the region. It is therefore necessary that young farmers are targeted through a combination of individual, group and mass media methods, for enhancing innovation dissemination and uptake. We recommend that the Government of Ghana allocates adequate resources to make agricultural extension delivery more effective and reliable.

Cloning of maize chitinase 1 gene and its expression in genetically transformed rice to confer resistance against rice blast caused by Pyricularia oryzae.

Fungal pathogens are one of the major reasons for biotic stress on rice (Oryza sativa L.), causing severe productivity losses every year. Breeding for host resistance is a mainstay of rice disease management, but conventional development of commercial resistant varieties is often slow. In contrast, the development of disease resistance by targeted genome manipulation has the potential to deliver resistant varieties more rapidly. The present study reports the first cloning of a synthetic maize chitinase 1 gene and its insertion in rice cv. (Basmati 385) via Agrobacterium-mediated transformation to confer resistance to the rice blast pathogen, Pyricularia oryzae. Several factors for transformation were optimized; we found that 4-week-old calli and an infection time of 15 minutes with Agrobacterium before colonization on co-cultivation media were the best-suited conditions. Moreover, 300 μM of acetosyringone in co-cultivation media for two days was exceptional in achieving the highest callus transformation frequency. Transgenic lines were analyzed using molecular and functional techniques. Successful integration of the gene into rice lines was confirmed by polymerase chain reaction with primer sets specific to chitinase and hpt genes. Furthermore, real-time PCR analysis of transformants indicated a strong association between transgene expression and elevated levels of resistance to rice blast. Functional validation of the integrated gene was performed by a detached leaf bioassay, which validated the efficacy of chitinase-mediated resistance in all transgenic Basmati 385 plants with variable levels of enhanced resistance against the P. oryzae. We concluded that overexpression of the maize chitinase 1 gene in Basmati 385 improved resistance against the pathogen. These findings will add new options to resistant germplasm resources for disease resistance breeding. The maize chitinase 1 gene demonstrated potential for genetic improvement of rice varieties against biotic stresses in future transformation programs.

Grain level characterization of widely cultivating traditional and new improved rice (Oryza sativa L.) varieties of Sri Lanka using physical and chemical test methods

Grain level characterization of widely cultivating traditional and new improved rice (Oryza sativa L.) varieties of Sri Lanka using physical and chemical test methods