Effects of Plant Parts on the Grain Yield, Kernel Weight, and Plant Height of Wheat and Barley¹

Abstract

A field study was conducted on dry land to determine the contribution of different plant parts to the kernel development of wheat and barley. Shading of the spike proved to be the most effective treatment in reducing the grain yield and 1000‐kernel weight of wheat and barley. The least significant effect was obtained by the removal of the lower leaves. Treatments made 1 week before anthesis caused maximum reductions in grain yield and 1000‐kernel weight. Plant height was least affected by shading or removal of the different plant parts. Clipping full awns at anthesis had the most significant effect on the grain yield and 1000‐kernel weight of wheat, reducing the yield 20.8% and the weight 13.4%. This reduction corresponded to the proportion of the awns clipped and the advancement of the stages of growth studied. The plant height was not affected by clipping the awns.

Effects of Removal of Some Photosynthetic Structures on Some Yield Components in Wheat

“…According to results obtained; flag leaf removal significantly reduced number of grains per spike, grain weight per spike and 1000-grain weight, and it is in agrement with reports of Saghir et al (1968), Mohiuddin and Croy (1980), Das and Muhkerjee (1991), Mahmut et al (1991), and, Sen et al (1996). Mahmood et al (1991) reported 16.1% reduction in grain yield after flag leaf removal at the heading.…”

“…Several studies have been conducted to study the effects of different plant parts on wheat kernel development. (Saghir et al 1968, Hsu and Walten 1971, Ledent and Moss 1979, Winzeler et al 1989, Blade and Baker 1991, Chowdhry et al 1999). …”

Efeito da presença das plantas daninhas no microclima da cultura da cevada

“…A hab ili dad e da pla nta par a obt er luz, águ a e nu tr ie nt es pa ra o se u cr es ci me nt o freqüentemente determina o sucesso da cultura no ambiente (Saghir et al, 1968). A competição entre plantas começa quando um ou mais recursos do meio (luz, água e nutrientes) são insuficientes para ambas.…”

“…Morishita et a1. (1991) afirma que a disponibilidade de água do solo, freqüentemente, é o recurso que mais limita o crescimento de plantas em ár ea s ag rí co la s. Do is me ca ni sm os qu e determinam o potencial de crescimento da planta, quando os recursos hídricos são limitados, são a extensão do sistema radicular e a eficiência de uso da água (Saghir et al, 1968). Os estudos de Peters (1968) No entanto, são poucos os trabalhos que procuraram determinar a importância relativa da competição pelos vários fatores de crescimento na competiçã o do efei to total das plantas daninhas sobre as plantas cultivadas.…”

RuBP carboxylase activity in wheat following ear emergence and evaluation of the role of ear

“…Studies also showed that ear photosynthesis was important but its contribution was variously estimated [10,12]. Most estimates of the ear contribution are based on defoliation or shading experiments [7,10]. Furthermore the studies were largely performed in pot culture where most of the leaves are sufficiently exposed to light.…”