The effects of pH, salinity, age of leaves, post-harvest storage duration, and psyllid infestation on nutritional qualities of giant leucaena fodder

Giant leucaena (Leucaena leucocephala subsp. glabrata) can be managed as a profusely branched bushy plant by repeated harvest of its foliage for use as fodder. The objective of this research was to determine the effects of soil pH and salinity, age of the leaves, post-harvest storage duration, and psyllid infection on the nutritional qualities of leucaena fodder. To determine the effects of soil pH and salinity on fodder quality, giant leucaena K636 plants were grown in large pots containing soils adjusted to different pH and salinity levels. The effects of age of the leaves, post-harvest storage duration and psyllid infection on fodder quality were studied using leucaena samples collected from Waimanalo Research Station. Among five pH levels tested, pH 6.0 was found to produce the highest amounts of protein and structural fibers in the foliage. Mimosine contents were highest at pH 6 and 7 and lowest at pH 5.0. The growth of giant leucaena was retarded and the nutritional quality were adversely affected under salinity conditions. Compared to young leaves, old leaves contained 18.5% less protein, 95% less mimosine, 30% less tannin and 40% more structural fibers. Post-harvest storage duration up to 72 h, at room temperature did not seem to affect protein, tannin and structural fiber contents of the foliage; however, mimosine content was reduced by 25%. These results will help to identify ideal soil pH, age of foliage, and post-harvest storage duration for obtaining high forage yield and nutritional quality for giant leucaena.

Evaluation of stability in maize hybrids using univariate parametric methods

Genotype × environment interaction is one of the complex issues of breeding programs to produce high-yielding and compatible cultivars. Interaction of genotype × environment and make the more accurate selection, the performance and stability of hybrids need to be considered simultaneously. This study aimed to investigate stable genotypes with yield using 12 maize hybrids in different climatic conditions of Iran. The experimental design used was a randomized complete blocks design in three replications in two cropping years in Karaj, Birjand, Shiraz, and Arak stations. The simple analysis of variance performed on grain yield of genotypes indicated that all hybrids studied each year and station were significantly different in grain yield. Also, the combined analysis results showed a significant effect on the environment, the effects of genotype, and the interaction of genotype × environment and t in the studied hybrids different. Comparing Duncan's mean on the data obtained from the research, KSC705 genotypes with an average yield of 7.21 and KSC704 genotype with an average yield of 7.04 were identified as high yield cultivars. In order to identify stable cultivars, six stability parameters were used. KSC260 and KSC707 genotypes had stability Based on the environmental variance, also had stability based KSC705, KSC707 genotype on environmental the coefficient of variation, and KSC260 genotypes had stability based methods of genotype and environment interaction. As well as based on Eberhart and Russell regression coefficient had the stability to KSC400 and SC647 genotypes. Also, they were identified as the most stable genotypes based on the detection coefficient method, KSC707, and KSC703 genotypes.