Open Access Original Research Article

Genetic Gains to Grain Yield of Maize Varieties for Small Farmers in Brazil

Ana Paula Cândido Gabriel Berilli, Rafael Nunes de Almeida, Luis Eduardo Gottardo, Monique Moreira Moulin, Messias Gonzaga Pereira, Sávio da Silva Berilli, Julio Cesar Fiorio Vettorazzi, Roberto dos Santos Trindade, Robson Ferreira de Almeida

Journal of Experimental Agriculture International, Page 1-12
DOI: 10.9734/jeai/2020/v42i1230622

The demand for expanding the genetic base in working collections of older maize breeding programs points to the need to pool efforts and reaffirm methodologies for conserving genetic variability that can still be accessed in maize populations. The objective of the work was to select full sib maize progenies and to estimate genetic gains in the first cycle of reciprocal recurrent selection for common maize intended for cultivation in a region characterized by family farm, in Brazil. We evaluated 120 full sib families of maize from crossbreeding between individuals of the Cimmyt and Piranão varieties. Competition trials were conducted at two experimental stations in the state of Espírito Santo, Brazil. A randomized block design was adopted with 2 repetitions, arranged in sets. Different selection indexes were tested in order to enhance gains in productivity and prolificacy. The selection of 40 superior families made it possible to estimate a gain of 0.77 Mg ha-1 in grain productivity for producers in the region. With these results, we discussed the importance of work to improve maize populations for small producers to motivate the conservation of the genetic variability of tropical maize germplasm. Thus, from the results obtained in this study, we show the possibility of investing in technologies aimed at small producers in order to motive the conservation of genetic resources, food sovereignty of producers and, consequently, world security, given the importance of this culture for human feed.

Open Access Original Research Article

Challenges and Coping Strategies in the Uptake of the System of Rice Intensification Practices in Oluch Irrigation Scheme, Homa-Bay County, Kenya

Matilda A. Ouma, Justus M. Ombati, Christopher A. Onyango

Journal of Experimental Agriculture International, Page 13-25
DOI: 10.9734/jeai/2020/v42i1230624

System of rice intensification (SRI) is a novel technological approach aimed at improving rice productivity using environmental-friendly and cost-effective agronomic practices. Although its utility has been demonstrated in several settings in sub-Saharan Africa, its implementation is still considerably low. This study explored the challenges faced and coping strategies used by Kenyan smallholder farmers who contribute substantially to domestic rice production, in the uptake of SRI practices in rural setting in the western part of the country where it was previously been introduced. The study involved a survey of 101 smallholder rice farmers in Oluch Irrigation Scheme in Homabay County, to understand the challenges and coping strategies to the uptake of the system of rice intensification practices. Descriptive and inferential statistical analysis was done to guide in summarising the results using the SPSS package. The findings revealed that a host of challenges impede the acceptance of SRI in Oluch irrigation scheme, mainly insufficient knowledge, shortage and high costs of labour, weak stakeholder networks in the rice value chain; pests and diseases; and high cost of agricultural inputs to facilitate SRI. Notably, none of these challenges were overwhelmingly prevalent across majority of farmers, but that they were accosted by multiple complex and competing challenges limiting their opportunities for uptake of different SRI practices. It was observed that the nature and manifestation of these challenges necessitated the involvement of multiple actors in the rice value chain to address them. This formed the basis for a multi-stakeholder approach to address challenges that limited the implementation of new agricultural technologies, especially the utility of innovative approaches such as innovation platform to promote the uptake of SRI.

Open Access Original Research Article

Quality of Grain Sorghum Seeds Coated with Different Combinations of Materials

Vanessa Aparecida Pereira Batista, Henrique Duarte Vieira, José Inácio Coelho Pires, Danilo Força Baroni, Flávio Wirlan Andrade da Silva

Journal of Experimental Agriculture International, Page 26-38
DOI: 10.9734/jeai/2020/v42i1230626

Sorghum (Sorghum bicolor) is the fifth most cultivated cereal in the world, has high liquidity in the market due to its nutritional and edaphoclimatic characteristics, however, because it is cultivated in marginal conditions, it presents productivity below its potential. The seed coating technique appears to optimize the cultivation of sorghum. The objective of this work was to analyze the quality of graniferous sorghum seeds coated with different filling materials and proportions of glue as a cementing material. After covering, the physical and physiological characteristics of the seeds and the initial development of plants in the greenhouse were evaluated. It was found that the coating with calcium silicate provided the best physical characteristics to the seeds with the highest adherence rates, total area, maximum and minimum diameter. The coatings with dolomitic limestone and dolomitic limestone + sand provided the best physiological performance of the seeds with the highest germination values ​​and root dry matter. The proportion of cementitious material 3: 1 provided good results in addition to being more economical. It is concluded that the combination of the filling material and the cementing material used in the coating of graniferous sorghum seeds interferes with their physiological performance and physical aspect.

Open Access Original Research Article

Spatial and Temporal Effects of Kenaf (Hibiscus cannabinus L.) Cultivation on Weed Dynamics in Southern Agro-ecologies of Nigeria

O. A. Aluko, T. O. Oyebola, J. O. Amosun, A. Adewunmi, T. T. Oluwayemi

Journal of Experimental Agriculture International, Page 39-47
DOI: 10.9734/jeai/2020/v42i1230629

Weed spectrum in Kenaf fields revealed the heterogeneous flora richness of agro-ecologies and potential weed challenges. A study was conducted in the Institute of Agricultural Research and Training (IAR&T), Obafemi Awolowo University Ibadan and other substations (Ilora, Ikenne and Kishi).  The effects of varied kenaf planting dates, genotypes and locations on weed dynamics and potential weed problem was investigated. Five Kenaf genotypes (Cuba 108, Ifeken DI 400, Ifeken 100, Ifeken 400 and Tianung 2) were planted. It was a 3 x 4 x 5 factorial experiment arranged in Randomized complete block design (RCBD) with three replicates. Forty five (45) weed species were identified across seventeen (17) plant families. Weed morphology comprised of broad-leaf weeds (71.11%), grass weeds (17.78%), sedge (6.67%) and spiderwort (4.44%). Abundance        of broad-leaf weeds (71.11%) mostly annual, reflected regular weed control from frequent     cropping patterns and agro-ecological variations. Panicum maximum, Ageratum conyzoides,  Tridax procumbens, Mitracarpus villosus, Spigelia anthelmia L. and Mimosa pudica were present in the locations. Commelina erecta, C. bengalensis, Cyperus rotundus, Cyperus esculentus and Maricus alternifolius, though scanty, they were difficult-to-control weeds. Summary of weed flora richness showed that Ibadan and Ilora had thirty one (31) weed each. This represented 68.89% of the recorded weed flora composition (45) in all locations. Kishi and Ikenne had ≤ 50% of the overall weed composition recorded. This might be due to cultural practices, weed dominance and agro-ecological variance. High percentage of broad-leaf weeds (≥60%) at all locations, might resulted to keen Kenaf-weed competition due to similarity in morphology and narrows weed control option. Cultural practices, high weed fecundity, short weed life cycle (mostly annual weeds), and wide dispersal corridor in the locations maybe implicated. Weed density and weed dry weight were similar across genotypes in all locations. Ibadan had the highest weed density with the lowest weed dry weight. Ilora and Kishi had comparable weed density. Notwithstanding, highest weed dry weight was recorded in Kishi, while the lowest was recorded in Ilora. This might be due to planting dates, weed types and differences in agro-ecologies.