Evidence of Improving Yield and Yield Attributes Via Half-sib Family Recurrent Selection in Maize (Zea mays L.)

Abstract

Recurrent selection is a cyclical selection procedure for improving the mean performance of plant populations. The goal of current research was to determine genetic variability, heritability, selection differential, expected response, percent gain cycle -1 and genotypic and phenotypic correlations among various traits. Sixty four half sib recurrently selected families derived from CIMMYT maize population CZP-132011 were evaluated in 8×8 square lattice design with two replications at Cereal Crops Research Institute (CCRI), Pirsabak during 2017. Data were noted on ear plant -1 , ear length, ear diameter, grain rows ear -1 , grains row -1 , 1000 grain weight and grain yield. Results showed highly significant differences among half sib families for all the studied traits. High heritability (h 2 ˃ 0.60) was recorded for all traits except 1000 grain weight which exhibited moderate heritability. High index of variation (I.V ˃ 1.00) was observed for all traits. Based on heritability and selection differential, the expected response was negative for plant height (-2.81 cm) and ear height (-5.22 cm), while positive expected response was recorded for ears plant -1 (0.15), ear length (1.48 cm), ear diameter (0.30 cm), grain rows ear -1 (1.30), grains row -1 (2.94), 1000 grain weight (14.19 g) and grain yield (153.04 kg ha -1 ). After one cycle of recurrent selection in these half sib families, the gain cycle -1 was recorded negative for plant height (-2.34%), ear and height (-4.90%),while positive gain cycle -1 was observed for ears plant -1 (3.26%), ear length (3.06%), ear diameter (4.99%), grain rows ear -1 (2.57%), grains row -1 (7.84%), 1000 grain weight (5.87%) and grain yield (4.17%).Grain yield exhibited significant and positive correlation with ear length (rG = 0.50** and rP = 0.33*) both at genotypic and phenotypic levels. Based on the findings of current experiment, it could be concluded that improvement in half sib families through recurrent selection method was found effective and population CZP-132011 has the potential of improvement through further recurrent selection. K e y w o r d sExpected response Half sib families Heritability Recurrent selection Zea mays L.

Cyclical response of maize populations versus base population and standard genotypes across environments

“…Los genotipos revelaron una mayor variabilidad genética entre los lugares y las fechas de siembra, las cuales pueden ser utilizadas para identificar y mejorar las poblaciones cíclicas de maíz. Se registraron variaciones significativas entre las poblaciones seleccionadas de maíz S 1 para la longitud de la planta, mazorcas por planta, hileras de grano por mazorca, peso de mil granos y rendimiento de grano (Sohail et al, 2018;Sheikh et al, 2019 optimum planting at CCRI) (table 3). The improved population -C 2 with delayed planting at UAP (73.33 days) and CCRI (73.67 days), check genotype Jalal with delayed planting at UAP (73.67 days), population -C 1 with delayed planting at CCRI (74.67 days) and UAP (75.33 days) revealed the lesser and same number of days to silking.…”

“…Genotypes revealed greater genetic variability across the sites and planting dates, which can be utilized for identification and improving the maize cyclical populations. Significant variations were recorded among the selected maize S 1 populations for cob length, cobs per plant, grain rows per cob, thousand kernels weight and grain yield (Sohail et al, 2018;Sheikh et al, 2019). Genotype x environment relationships revealed significant variations for flowering and yield variables which authenticated that maize populations could not sustain uniform phenotypic behaviour over diverse envi ronments (Sajjad et al, 2020a, b).…”

“…La selección recurrente fortalece los genes deseables para los rasgos poligénicos, y genéticamente mejora los recursos del germoplasma del maíz (Sajjad et al, 2020c male and female flowering, and plant and cob height, while enhancement in yield variables with in maize S 1 selection (Kolawole et al, 2017). The S 1 recurrent selection exhibited significant positive response with higher grain yield in contrast to selfed and origional genotypes in Zea mays L. (Sohail et al, 2018).…”

“…Estudios anteriores reportaron una significante disminución en precocidad y rasgos morfológicos tales como los días para la floración masculina y femenina, y longitud de la planta y de la mazorca, mientras que se mejoran las variables de rendimiento en la selección S1 de maíz (Kolawole et al, 2017). La selección recurrente S1 mostró una respuesta positiva significativa con un mayor rendimiento de grano en contraste con los genotipos autóctonos y originales en Zea mays L. (Sohail et al, 2018).…”

Impact of half-sib family recurrent selection on grain yield in maize population ZM-309

“…Due to highly allogamous nature it does not survive in wild form. From nutrition point of view, maize is composed of 66.8% starch, 9.9% protein, 4.7% oil, 8.6% fiber, 3% suger, and 7.1% ash [2]. Industrially maize can be used for development of starch, tanning material, alcohol, oil and polishes, etc.…”