Analysis of growth, productivity and yield in rainfed field-grown maize plants

Abstract

Analysis in growth, productivity and yield in two maize genotypes (DTP drought tolerant population and line В 73) have been done in rainfed field conditions. The trial was carried out during different stages of development and several parameters of water status (water potential and soil water content), crop growth and productivity (relative leaf expansion rate - RLER relative growth rate - RGR, net assimilation rate - NAR and leaf area ratio - LAR) and components of yield (ear length, row number per ear, grain number per row, ear weight, kernel weight and weight of 1000 kernel) were measured. Obtained results of crop water status pointed out that plants were exposed to mild stress field conditions and also indicated that in this conditions investigated plants may have a chemical signaling regulation mechanism. Growth and productivity analysis of both genotypes showed that leaf area and total biomass were increased during the season and reached maximal values at milky stages. The highest values of RLER, RGR and LAR were observed in the vegetative stage and decreased during the end of season. Drought had smaller effect on inhibition of leaf growth, productivity and yield in drought tolerant population DTP Comparing to drought susceptible line В 73.

Analiza rastenja, produktivnosti i prinosa kod dva genotipa kukuruza (DTP populacija tolerantna na sušu i linija В 73) urađena je u polju u uslovima suvog ratarenja. Eksperiment je izveden u različitim fazama ontogeneze ispitivanih biljaka. Praćeni su parametri vodnog režima (vodni potencijal i sadržaj vode u supstratu), rastenja i razvića (relativna brzina lisne ekspanzije - RLER, relativna brzina rastenja - RGR, brzina neto asimilacije - NAR i relativna lisna površina -LAR) i komponente prinosa (dužina klipa broj redova po klipu, broj zrna po redu, masa klipa, masa zrna i masa 1000 zrna). Rezultati merenja parametara vodnog režima su pokazali da su biljke u poljskim uslovima bile izložene umerenom stresu suše, kao i da su fiziološki procesi u tim uslovima bili pod dejstvom mehanizama hemijske regulacije. Analiza rastenja i produktivnosti kod oba genotipa je pokazala da su se ukupna lisna površina i biomasa povećale u toku sezone i dostigle maksimalne vrednosti u fazi mlečnog zrenja. Najveće vrednosti RLER, RGR i LAR su utvrđene u vegetativnoj fazi i one su opadale do kraja sezone. Suša je imala slab efekat na inhibiciju rastenja listova, produktivnosti i prinosa kod populacije tolerantne na sušu u poređenju sa linijom В 73 koja je genotip osetljiv na delovanje suše.