Agronomic performance of castor under different growing conditions

Abstract

Castor has emerged as an oilseed species capable of meeting the demand of the Brazilian market.Thus, there is a need for studies to evaluate the different growing conditions that this species can be cultivated in order to subsidize their production. The study aimed to evaluate the influence of different growing conditions on agronomic performance of seven castor bean cultivars grown in Savanna-Pantanal ecotone region. The trial was conducted at Universidade Estadual de Mato Grosso do Sul, Aquidauana Campus. Treatments consisted of seven castor bean cultivars (BRS Energia, IAC-2028, IAC-Guarani, BRS Nordestina, BRS Paraguaçu, IAC-80 and IAC-226) and three growing conditions (with weed control and without topdress nitrogen; with topdress nitrogen at 80 kg ha -1 and with weed control; without weed control and absence of topdress nitrogen) in two agricultural years (2011 and 2012), arranged in randomized block design with three replications in factorial arrangement (7 x 3 x 2). The following variables were evaluated: plant height, stem diameter, number of bunches, number of fruits and fruit yield. The cultivars BRS Energia, IAC 2028, IAC Guarani and BRS Paraguaçu obtained greater fruit yield. Topdress nitrogen and weed control provided to cultivars the highest stem diameter, number of bunches, number of fruits and fruit yield.

Growth and Yield of Castor Hybrids at Varying Nitrogen Levels in Andhra Pradesh

“…But under limited availability of nitrogen reduced cell divison and elongation occurs which ultimately reduced the plant height. The results obtained in present study are in close agreement with Torres et al, (2016) and Hanumanthappa et al, (2011).…”

“…The present results are in conformity with those of Torres et al, (2016) and Man et al, (2017). Based on this study, it can be concluded that cultivation of castor variety PCH 111 and GCH 4 with 120 kg N ha -1 has recorded higher growth and yield parameters and bean yield in Andhra Pradesh under rainfed condition.…”

Critical phosphorus levels and availability for castor oil plant grown in different soil classes of Brazil

“…The P possibly added to the soils was preferentially adsorbed by soil colloids, in order to form P-Al and P-Fe and precipitate with calcium found in the soil, which formed P-Ca Mehlich-1 extracted larger P amounts than those of Resin, and the extraction was inversely proportional to the clay content. Torres et al, (2016) found higher Mehlich-1 efficiency in comparison to that of the Resin when they evaluated Hapludox with 800 g kg -1 clay. The ion-exchange Resin was poorly influenced by the soil buffering capacity and showed no extractor wear.…”

“…Thus, Mehlich-1-recovered P levels may have been overestimated because the extractor can displace P bound to Ca, Fe and Al oxides, which are unavailable forms to plants. According to Torres et al, (2016), acid extractors predominantly dissolve P when it is attached to Ca. Small P amounts bound to Fe and Al, depending on phosphates solubility features, allowing for inferring whether extractors are less suitable acids for humid tropical region soils, which have kaolinite, iron and aluminum oxides prevalence in the soil clay fraction.…”

“…Suboptimal P fertilizer input may lead to poor growth and malfunctioning in plants, whereas over optimal P input may lead to low P efficiency (Ma et al, 2012). Most Brazilian soils have high weathering degree, large iron and aluminum oxide amounts and clay belonging to the kaolinite minerals group, which is characterized by surface charges presence, varying according to the soil solution reaction (Torres et al, 2016). Thus, soil can work as P source, showing good P input capacity to plants, or as drainer, since it strongly competes for P in the plant and leaves.…”