Response to salinity of three grain legumes for potential cultivation in arid areas

Abstract

The material balance of all the chemical species associated with the phosphate sorption reaction by two amorphous clays, silica-alumina gel and synthetic goethite was investigated adjusting the initial pH to 4.0, 5.0, 6.0, and 7.0. Phosphate sorption was found to decrease with increasing initial pH. During phosphate sorption, the equilibrium pH rose, adsorption of Cl^- decreased to a state of negative adsorption, adsorption of Na⁺ increased markedly, silicate was released, and Al in the solution was precipitated. With increasing initial pH, the amount of apparent released OH^- increased, the amount of Na⁺ adsorption increased, and the amount of released silicate decreased. The overall relationship of the material balance is explained in terms of the charge balance associated with phosphate sorption.     

Survey of Underutilized Grain Legume Production Systems in the Southwest Agricultural Zone of Nigeria

ABSTRACT

A socio-economic survey of production systems was carried out in four out of the eight states that make up the southwest agricultural zone of Nigeria. A total of 157 minor grain legume farmers selected by multi-stage sampling were interviewed using structured questionnaires. The study shows that lima bean, pigeon pea, African yam bean, and bambara groundnut are the prominent minor grain legumes grown on less than 10% of the total cultivated land area. The minor grain legumes are grown on an average land size ranging from 0.2 to 0.4ha and predominantly in mixture with crops like cassava, maize, yam, sorghum, cocoyam, etc. The use of modern inputs like herbicides, pesticides, fertilizers, and improved varieties is uncommon in minor legume production systems. The cultivation of these legumes is more popular among the older members of the farming communities, about 78% of which are above 40 years of age. The average yield of the legumes on farms is considerably low, estimated at 271kg/ha, 265kg/ha, 174kg/ha, and 275kg/ha for lima bean, pigeon pea, African yambean, and bambara groundnut, respectively. Major constraints identified by the farmers include low market demand, inadequate seed supply, high cost of labour, and low yield. Research work is therefore needed in agronomy and breeding for improved yield and utilization for expanded market and, consequently, increased production.     

Cryptic diversity,multilocus phylogeny,and pathogenicity of cercosporoid fungi associated with common bean and cowpea

In recent years, common bean (Phaseolus vulgaris) and cowpea (Vigna unguiculata) plants in the north of Iran have exhibited symptoms resembling Cercospora leaf spot (CLS) disease. This study was initiated to elucidate the taxonomy and pathogenicity of cercosporoid taxa associated with leaf spot diseases of these two legume crops in Iran. A total of 138 samples with CLS symptoms were collected from cultivated common bean and cowpea species in northern Iran and subjected to microscopic examination, resulting in identification of 98 Cercospora and 59 Pseudocercospora samples. A six-locus phylogenetic analysis (ITS, actA, tef1, gapdh, his3, and cmdA) coupled with examination of the morphology of 42 representative isolates from these samples confirmed that several cercosporoid fungi occur on common bean and cowpea in Iran. Five Cercospora species (C. iranica, C. cf. flagellaris, Cercospora sp. G, Cercospora sp. T, and C. vignigena) and two Pseudocercospora species (P. griseola f. griseola and P. cf. cruenta) were found; of these, C. cf. flagellaris was the dominant species, occurring on both common bean and cowpea. Pathogenicity tests confirmed that all seven species could infect leaves of common bean and/or cowpea. This is the first report of C. iranica, Cercospora sp. G, and Cercospora sp. T associated with common bean and/or cowpea in the world. In addition, C. vignigena was recorded for the first time in Iran. Results achieved in this study will assist strategies for the management of CLS disease of common bean and cowpea.     

Global status of nematode problems of groundnut, pigeonpea, chickpea, sorghum and pearl millet, and suggestions for future work

Analysis of responses received from 40 cooperators in 20 countries to a questionnaire on nematode problems of groundnut, pigeonpea, chickpea, sorghum and pearl millet suggested that Meloidogyne spp. are internationally important nematode pests of groundnut, chickpea and pigeonpea. Pratylenchus spp. are important on all the five crops. In India, Heterodera cajani and Rotylenchulus reniformis are important pathogens of pigeonpea. Over the last 10–15 years, extensive nematode disease surveys have been undertaken for these crops in Australia, Egypt, India, Jamaica, Senegal, Sudan, Thailand and Zimbabwe; however, < 10% of the total crop areas were covered by these surveys. Except for Brazil, Egypt, USA and Zimbabwe, growers do not use nematicides to control the nematodes. Cultural practices, especially crop rotations, are the most commonly used control measures. Species of Meloidogyne, Pratylenchus and Rotylenchulus on the legumes, and species of Hoplolaimus, Pratylenchus, Quinisulcius and Xiphinema on the cereals, are strongly suspected of increasing the severity of fungal diseases. Work aimed at finding host resistance is being done in Brazil, Fiji, India and the USA, and some sources of resistance have been identified against Meloidogyne arenaria, M. incognita, M. javanica and R. reniformis. Facilities for resistance screening work now exist in many countries. Information on damage thresholds of important pest species are available only from Brazil, Fiji, India and the USA.     

Hard seed breakdown patterns of unprocessed forage legume seed sown into dry soil in summer in southern Australia

The patterns and extent of hard seed breakdown of dormant seeds and pods following burial in the soil in February (summer) varied for up to 19 accessions of 12 species of annual forage legumes. The experiments, at six sites across southern Australia, were designed to identify legumes whose patterns of hard seed breakdown would suit them to agronomic evaluation in a summer sowing research program. For a subset of accessions, sufficient hard seed breakdown was demonstrated between February and April to allow a high proportion of seed to germinate in late autumn—a desirable pattern for summer sowing. Although there was a large G x E interaction, some cultivars of Ornithopus sativus Brot., O. compressus L. and Trifolium spumosum L. had a pattern that was reproducible at all sites. The experiments also identified accessions of Biserrula pelecinus L. and T. glanduliferum Boiss., which had the desirable pattern in regions of south‐eastern Australia, but not Western Australia. A pragmatic approach for selection of forage legume accessions in situ for evaluation within a summer sowing program was demonstrated.     

清洁型草本纤维生物提取工艺的污染机理研究

【目的】研究草本纤维生物提取过程中的物质变化规律,为草本纤维生物提取废水处理提供依据。【方法】在草本纤维原料生物脱胶、生物制浆过程中,分别采用高锰酸钾法、重量法、膜分离技术、DNS和考马斯亮蓝比色法测定了各类物质的变化规律。【结果】草料发酵阶段微生物可消耗占草料总量10%左右的非纤维素物质;发酵以后通过水洗可除去占草料总量15%以上的非纤维素物质,其中分子量大于10 kD的颗粒状物质占90%,分子量小于10 kD的水溶性还原糖和蛋白质仅占10%。由此可以肯定,生物提取工艺不仅从源头上大幅度减少了污染物的排放量,而且因为该工艺中废水的水质单一、废水中污染物多呈颗粒状,可以通过物理分离方法除去,污染处理负荷大幅度减轻。【结论】草本纤维生物提取工艺,可以减少30%～60%有机污染物排放量,其污染物90%来自原料中的大分子颗粒或块状有机物脱落物。     

Integrating new soybean varieties for soil fertility management in smallholder systems through participatory research: Lessons from western Kenya

The aim of this paper was to understand the process of selecting soybean (Glycine max [L.] Merr.) promiscuous varieties by smallholders for soil fertility management in western Kenya. Eight varieties were screened on 2.5 m × 3 m plots that were managed according to farmers’ practices and evaluated through participatory monitoring and evaluation approaches. Farmers selected preferred varieties and explained their reasons (criteria) for making the selections. Seven promiscuous varieties had better yields than a local one. Farmers’ selection criteria fell into three broad categories relating to yield, appearance and labour. Selection criteria were not primarily aimed to improve soil fertility. This created a challenge to embed the new varieties within the local farming systems for soil fertility improvement. This study shows that farmer criteria for selecting varieties overlapped with scientific procedures. We propose co-research activities targeted to strengthen farmer experimentation skills, their understanding on N addition, and the role of P.     

合理施肥与红壤山地豆科牧草生长

施肥综述了山地红壤豆科牧草对N、P、K元素的需求特点以及施肥对豆科牧草生长的影响,并指出了需进一步加强研究的问题。     

Using farmers' criteria to assess profitability of fodder shrubs in the desert margins of West Africa

This paper presents the results of a study carried out in the Ségou region of Northern Mali to analyse the use of fodder shrubs. The farmer‐level fodder banks consisted of three perennial legumes (Gliricidia sepium, Pterocarpus erinaceus and Pterocarpus lucens). The main question addressed is whether this new type of fodder was more profitable for smallholder farmers compared to alternative fodder options. To test hypotheses for profitability, farmers were grouped in two different ways. The first grouping was based on the different village communities the farmers belonged to. The second grouping consisted of three user groups based on individual (non‐) use patterns of the fodder banks. ‘Passives’ were non‐users because of apparent disinterest. ‘Actives’ were the group of users whose fodder banks performed well and who harvested in time while ‘Unfortunates’ were non‐users unable to harvest fodder mostly through high mortality rates of the shrubs. Profitability was measured by increases in income or increases in the productivity of labour spent on feeding livestock. Profitability was shown to be dependent on the use pattern of the fodder shrubs. In the actual situation no user group had gained any concrete financial benefits. The several scenarios in which other use modalities were modelled, did show gains of using fodder shrubs, but only under conditions where alternative options were expensive. The perceived value of this technology was high. The use patterns indicated that this did not necessarily reflect farmers' long term interest in the technology itself. Rather, farmers were motivated by perceived opportunities to gain short term material and social benefits from the project promoting the shrubs. Copyright © 2007 John Wiley & Sons, Ltd.     

兰州地区牧草引种试验研究

通过调查牧草生育期、产草量、株高、生长速度等生育指标,对国内外３７份（豆科６个种,共１２个品种;禾本科１４个种,共２５个品种）牧草进行引种试验研究。结果表明：干物质产量较高且适应性强的豆科牧草为Ｑｉｎｇｙａｎｇ紫花苜蓿、Ｒａｊａｈ和Ｖｅｓｎａ红三叶、鹰嘴紫云英、鹰嘴豆等５种（品种）牧草。禾本科中表现较好的一年生牧草为大黍草,多年生牧草干物质产量自高向低依次为Ｌａｕｒａ牛尾草、Ｇａｎｓｕ和Ａｍｂ鸭茅、Ｇｏｎｄｏｌｉｎ和Ｂｃｈｏ紫羊茅、Ｂｉｌｂｏ猫尾草、Ｑｉｎｇｈａｉ牛尾草、Ｍａｎｄｉｎｇ苇状羊茅、Ｇｏｎｄｏｌｉｎ紫羊茅、Ｇａｎｓｕ猫尾草、狼尾草、布顿大麦等。