Nitrogen fixation and seed yield of winged bean (Psophocarpus tetragonolobus (L.) DC) under various support systems

A field experiment was carried out to determine the effects of support systems (0, 1, and 2-m height) on nodulation, nitrogenase activity, accumulation and partitioning of total nitrogen (N) and seed yield of a local cultivar of winged bean (Psphocarpus tetragonolobus (L) DC) Plants grown with 2-m supports produced substantial nodule mass, the highest rate of nitrogen fixation, increased nitrogen accumulation of the plant, and seed yield compared to those grown with 2-m supports and unsupported plants Nitrogenase activities increased and reached a peak at the onset of flowering i.e. 70 days of growth (D70) but declined during the pod formation stage in plants grown with a support system. On the contrary, unsupported control plants recorded a peak nitrogenase activities 14 days before flowering The descending order of total plant nitrogen accumulation at D140 was plants with 2-m supports (6 30 g N plant-1) > those with 1-m supports (4.06 g N plant-1) > control plants (2.10 g N plant-1), reflecting the beneficial effect of support systems on N9 fixation as mentioned earlier Supported plants contributed significantly higher leaf N at the vegetative stage Consequently, seed N was also significantly higher than in unsupported plants. There was a seven-fold increase in seed yield for plants grown on 2-m supports compared with unsupported plants. The beneficial effects of08-Jan-2015 yield of winged bean are discussed

Influence of elemental sulfur on nutrient uptake, yield and quality of cucumber grown in sandy calcareous soil

Abstract This study was carried out to investigate the effect of elemental sulfur (S 0 ) and sulfur oxidizing bacteria (Paracoccus versutus) on nutrient uptake, yield and quality of cucumber grown in sandy calcareous soils. Both elemental sulfur powder (S 0 P) and pellets of sulfur powder-Tiger 90 (S 0 T) were applied at rates of 0, 1, 5 and 10 t/ha at Al Hamraneya. On the contrary, S 0 P was used at rates of 0, 1, 5 and 10 t/ha combined with or without Paracoccus versutus (Pv) at Al Kuwaitat, United Arab Emirates (UAE). Higher concentrations of N, P, S, Mn and Zn in leaves and yield of cucumber at both locations were obtained with application of S 0 at rates of 5 and 10 t/ha. Total soluble sugar (TSS) content and vitamin C was higher with the application of S 0 at rates of 5 and 10 t/ha. Application of Pv individually or with varying levels of S 0 P had no positive effect on nutrients uptake, yield and quality of cucumber. A positive correlation was observed between shelf life and vitamin C. At Al Hamraneya S 0 P performed better than S 0 T. The results reveal that application of S 0 P at the rate of 5 t/ha in sandy calcareous soils can enhance the nutrients uptake ability, increase yield and superior quality of cucumber at both locations in UAE

MORPHOLOGICAL CHARECTERIZATION OF KENAF (Hibiscus cannabinus L.) IN MALAYSIAN TROPICAL ENVIRONMENT USING MULTIVARIATE ANALYSIS

ABSTRACT Kenaf (Hibiscus cannabinus L.) is a green resource of natural fibre. But our understanding of genotypic characteristics and relationships between kenaf genotypes grown up in certain environmental condition is limited, which is important for effective kenaf breeding program for mass commercial production and fundamental need for utilization of this resource. Thirty two kenaf genotypes originated from different parts of the world were cultivated in open field of Malaysian tropical environment. A total of 15 morphological data were collected and multivariate analysis was used to identify the genetic variation among the genotypes. There were significant differences among the genotypes in fibre weight, days to 50% flowering and days to maturity. Principal component analysis showed that days to flowering, days to maturity, plant diameter and leaf shape were the traits responsible for major variation among the genotypes. In cluster analysis different kenaf genotypes produce three distinct groups which can be used for selection of parents of in the breeding program. From total three clusters, high yielding late mature genotypes of the cluster 3 can be used to cross with middle flowering genotypes of cluster 2 to produce relatively photo insensitive variety with better fibre and stick yield in Malaysian tropical environment