The net potential effect of severe changes in rainfall pattern disrupts crop production leading to food insecurity, loss of jobs, and poverty. Crop production in Niger State is predominantly rain-fed, thus, exposing this major livelihood activity to the variability of rainfall. The study examined the impact of rainfall variability and its consequences on crop production. This is to integrate climate change adaptation options into agricultural activities. Strategies for climate change adaptation options in the study area have often been made without experimental foundations placed on the level of rainfall variability and its implications on crop production. To achieve this, a climatic index (CI) analysis of rainfall was employed to ascertain the level of rainfall extremes occurrences resulting from rainfall variability using standard deviation as a tool for rationalization. The study also used crop yield to test the relationship between the yield and rainfall characteristics for thirty years (1990-2019). Rainfall data and crop yield (soybean, maize, and sorghum) were collected. The data were analysed using statistical and climatic index analyses. The results show that there were various degrees of rainfall extremes that occurred (from mild to severe dry spell and mild to severe wet spell). Moreover, the regression analysis shows that F-values > p-values. Consequently, the occurrences of severe wet spells and mild to severe dry spells impacted negatively on crop production, which undermines food security. Based on the findings, recommendations were made to mainstream the adaptation options.

Adequate information on genetic variance and nature of gene actions for yield component characters are very crucial for a successful breeding programme. In this study, genetic variance, heritability and number of effective genes were estimated for Some Spike Characters in Castor. Bi-parental crosses were made among six castor lines at the National Cereals Research Institute (NCRI), Badeggi, Nigeria. Forty five (45) plant samples of parents and F1, 120 F2 and 60 BC1 and BC2 of the three crosses were evaluated for estimation of the genetic variance, heritability and number of effective genes for the traits studied. The results revealed significant variability among the generations for the genetic analysis. The results showed that the magnitude of the environmental variance for all the traits in all the crosses was lesser than both additive and dominance variances except for the number of capsules per raceme in the Cross II. High heritability (h2> 60%), high magnitude of additive variance compared to dominance, high genetic advance (GA > 20%) were observed for total raceme length in all the crosses. Predominant dominance variance, low heritability and moderate average genetic advance (17.69%) were recorded in the crosses for the seed yield per plant. Number of capsules per raceme (CPR) was controlled by 4.47 to 20.96 genes among the crosses. Seed weight (SW) was controlled by a range of 3.13 to 25.16 effective genes. For seed yield (SY), a range from 27.50 to 52.29 effective genes was observed. These findings provide a guide on choice of selection procedures for the improvement of the traits studied.

Land is the most important endowment in nature, providing livelihood in both the agricultural and non-agricultural sectors. However, most areas of land previously developed from tropical rainforest have been degraded as a result of land misuse with nutrient mining and soil degradation presently considered as problems in arable farms. Hence, the extent to which land for crop production influences soil properties need to be studied to greater details due to variations in soils by location. The objective of the study is to investigate the effect of agricultural land use systems on the soil physical and chemical properties. Three representative fields with three replicates each which have been in active use for last 5 years were selected from each agricultural land use types: Cultivated (07.31° N 05.12° E 360.0 M), Agroforestry (07.31° N 05.21° E 373.5 M) and Grazing land (07.29° N 05.35° E 355.0 M). Five soil sub-samples were collected from the depths of 0-20 and 20 – 40 cm each in a radial sampling. The data was subjected to analysis of variance (ANOVA) using Statistical Analytical System (SAS) and the means were separated using Duncan’s Multiple Range Test (DMRT) at P<0.05 significant level. The mean values of soil chemical properties are highest in the agroforestry land followed by cultivated and then in the grazing land. Grazing land shows the highest bulk density of (1.87 g/cm3), cultivated (1.30 g/cm3) and then agroforestry (1.24 g/cm3) with same trends recorded in particle density across the land use. The soils significantly responded to changes in land use systems through salient soil features which constitute soil properties governing soil fertility and productivity. Such human-induced change is not limited to surface soils but also the subsurface soils and has remarkable implication for ecosystem quality and productivity of the traditional low-external-input agriculture in the study area.

The mode of gene action for the expression of quantitative traits is decided by the predominance of variances due to additive, dominance and epistasis gene effects. In this experiment, involving four F1 crosses (TCH1716 x TCB37, TCH1705-101 x TCB209, KC2 x TCB26 and TSH0250 x DB3) of upland cotton, inheritance of major yield components by Generation Mean Analysis was investigated. The investigation revealed that both additive and dominance gene effects were involved in the expression of most of the yield contributing traits. One or more types of epistatic interaction effects were prevalent for all the characters and thus played a major role in the control of the characters. The inheritance of the traits was found to be complex in lieu of the low heritability estimates and genetic advance over mean. For seed cotton yield per plant, the dominance x dominance interaction effect was positively significant for all the crosses, the additive x dominance effect was positively significant only in cross 1 and the dominance main effect showed negative significant in all crosses. The dominance (h) and dominance x dominance (l) effects were of opposite signs in all the crosses indicating the presence of duplicate epistasis in all the crosses. To harness additive gene effects for improvement of some of the traits, breeding methods with postponement of selection to later generation should be adopted.