一个豇豆上的番茄黄化曲叶病毒分离物的分子鉴定及其基因组全序列

2008年秋,在上海郊区大棚栽培的豇豆上发现一种叶片褪绿和黄化病害症状。通过PCR从感病的植株叶片中扩增出番茄黄化曲叶病毒的全序列。序列比较及系统进化分析表明,这种病毒是菜豆金色黄花叶病毒属成员之一的TomatoYellwLeafCurlVirMs—Israel（TYLCV-IL）。基因组是由2781个核苷酸组成的环状单链DNA,具有典型的旧世界单组分菜豆金色黄花叶病毒属病毒的特征,有6个开放阅读框,V2和V1（外壳蛋白基因）在病毒链上,而C3、C2、C1和C4在互补链上。这是国内番茄黄化曲叶病毒侵染豇豆的首次报道。     

Performance of cowpea cultivars when grown as an intercrop with maize of contrasting maturities

A field trial was conducted during the rainy seasons of 2008 and 2009 at Samaru in northern Guinea savannah of Nigeria to determine the performance of semi-determinate and indeterminate cowpea cultivars intercropped with extra early, early and late maize cultivars. The trial was laid out in a randomized complete block design (RCBD) having treatments arranged as a split-plot factorial. Transmitted radiation was reduced by 49–63% due to shading by the maize plants. Similarly, intercropping cowpea with maize reduced intercepted radiation, fodder yield and grain yield of cowpea by 59–70%, 39–51% and 45–62%, respectively. Intercepted radiation and yields of intercropped cowpea were lower for late maize which maintained high leaf area over a longer period of time. This is supported by the higher plant height, higher leaf area index (LAI) and reduced transmitted radiation recorded in late maize compared with extra early and early maize. Extra early and early maize were less competitive with cowpea because of shorter period of association in addition to permitting higher radiation. Crop value of maize plus cowpea was higher than that of sole cowpea ($2616.8 vs. $1218.7 ha^?1) because higher combined yield was achieved by a more efficient use of resources in the intercrop. Therefore, cowpea cultivar may be intercropped with extra early maize.     

Uronic acid in humus

Introduction

Uronic acids are aldehydic sugar acids. In nature, they are composed mainly of d-glucuronic acid and d-galacturonic acid and scarcely of dmannuronic acid.     

Effects of heat on the removal of polyphenols and in vitro protein digestibility of cowpea (Vigna unguiculata (L.) Walp.)

Simple wet heat treatments like simple boiling (atmospheric pressure, 100 °C) and pressurized boiling (higher than 100 °C) reduced the polyphenol content of mature dark red seeds of cowpea (Vigna unguiculata (L.) Walp.) cultivar UPL Cp 3 by 61 to 80% and improved in vitro protein digestibility (IVPD) by 6 to 26%. Pressurized steaming (higher than 100 °C) removed 48 to 83% of the polyphenols but increased IVPD by only 1.1 to 4.2%. Dry heat as exemplified by roasting and microwave treatment inactivated 58 to 71% of the tannins but increased IVPD by only 1%. All the heat treatments were effective in removing/inactivating polyphenols though different responses were observed with the resulting in vitro protein digestibilities.     

茶树油清除豇豆农药残留的效果

为研究茶树油清除果蔬农药残留的效果,该试验选取豇豆为供试材料,以不同浓度的茶树油和水溶性茶树油等清洗处理,利用气相色谱和气相色谱-质谱联用检测豇豆内有机磷类、拟除虫菊酯类和氨基甲酸酯类的农药残留量,计算农药清除率。供试7种农药中,水胺硫磷、马拉硫磷、氧乐果、三唑磷、毒死蜱、氯氰菊酯和速灭威在豇豆中的初始浓度分别为:20.395、1.690、6.524、10.719、0.160、12.104和23.057mg/kg。茶树油处理后检测结果表明,茶树油具有清除残留在豇豆中农药的能力,清除效果随茶树油浓度增加而增强;清除有机磷类农药效果较拟除虫菊酯类和氨基甲酸酯类农药明显。茶树油比去离子水、市售果蔬农残清洗剂清除农药残留效果显著,同时,相同浓度的水溶性茶树油比相应茶树油清除农药残留能力强。0.8%水溶性茶树油清除效果最佳,清除率分别为水胺硫磷80.48%,马拉硫磷94.54%,三唑磷82.79%,毒死蜱84.58%,氧乐果72.20%,氯氰菊酯80.51%,速灭威72.21%。通过研究结果可知,茶树油可作为有开发前景的果蔬清除剂。     

夏秋豇豆斜纹夜蛾发生规律调查及其防治对策

2007年在浏阳市沿溪镇对夏秋豇豆田间斜纹夜蛾发生规律进行了调查,结果表明：豇豆上斜纹夜蛾的盛发期在7、8、9三个月,其发生高峰在7月25日-8月9日,9月13—23日。药剂防治应在7月25日开始,每5—7d喷一次,连续防治3—4次。     

Characterisation of thirteen cowpea landraces from Umbria (Italy). Strategy for their conservation and promotion

Thirteen landraces of cowpea (Vigna unguiculata (L.) Walp. subsp. unguiculata cv. gr. Unguiculata) have been morphologically and agronomically characterised as part of a plan for safeguarding and protecting plant biodiversity typical of Lake Trasimeno (Umbria, central Italy). Sixty plants per accession were scored for plant vigour, growth habit, flower colour, days to flowering, days to first mature pod, pod length, total number of pods produced, seed colour pattern, 100 seed weight, total seed yield and virus susceptibility. With the exception of vigour and growth habit, all landraces appeared to be well differentiated from one another for all the characters considered. Strategies and problems related to their in situ conservation are discussed.     

化学调控栽培综合措施对豇豆早期产量及品质的影响

通过运用五因子二次正交通用旋转组合设计 ,研究了氮肥 (N)、丰产素 (FCH)、萘乙酸 (NAA)、防落素 (PCPA)和密度 (D)对豇豆产量和品质的影响。结果表明 :这五因素对豇豆产量均有明显的影响 ,而且存在交互作用 ;氮肥、丰产素、萘乙酸能影响豇豆蛋白质含量 ;而氮肥、丰产素和防落素则是影响还原糖含量的主要因素。     

美国无架豇豆单株产量构成因素分析

[目的]明确影响单株产量的重要因素,为美国无架豇豆栽培以及良种繁育提供参考。[方法]定株调查每株美国无架豇豆的豆荚数、荚重、荚长、花序数,拉秧时测定主茎高、分枝数及主茎节数,并计算单株产量,进行单株产量构成因素的相关分析和通径分析。[结果]豆荚数对单株产量的影响最大,且主要是直接正效应;荚长对单株产量的直接正效应居第2位;花序数、分枝数、主茎高及主茎节数对单株产量的直接或间接影响都较小或微弱;所研究7个性状对单株产量的总贡献为0.938 1,说明没有漏掉影响较大的因素。[结论]生产中,从增加豆荚数着手来提高单株产量是直接而有效的,通过增大豆荚长度来提高单株产量也有一定效果。     

释放不同益害比多异瓢虫对设施豇豆豆蚜的防效及定殖影响

设施豇豆生产中常遭受豆蚜Aphis craccivora (Koch)为害,蚜害可导致豇豆产量、品质下降等问题出现。多异瓢虫Hippodamia variegata (Goeze)为豆蚜的重要天敌,在豇豆生产用温室内,按多异瓢虫和豆蚜益害比1:10、1:20、1:40、1:60及1:80比例分别释放多异瓢虫成虫;同时,设置未释放天敌对照区。调查豆蚜和多异瓢虫种群数量和结构动态变化,比较豆蚜虫口减退率、防治效果、多异瓢虫定殖率及种群增长率等指标,确定持续防治豆蚜的最佳益害比。结果表明,在按益害比1:10和1:20释放多异瓢虫5～35 d后,其对豆蚜防效可达90%以上;但防治后期多异瓢虫定殖率低,防治成本较高。按益害比1:80释放多异瓢虫3～7 d后,对豆蚜防效高于60%,释放后期防效持效期为7 d,防治后期瓢虫定殖率和种群定殖速度较高。益害比为1:60和1:80时防治后期防效低、持效期短,但定殖率高于其他益害比。益害比1:40则兼具防效好和定殖率高的特点,可持续控制设施豇豆豆蚜的为害,是最佳释放比例。推荐将1:40作为多异瓢虫防治豇豆上豆蚜的参考益害比。