Identification of four novel members of Kunitz-like α-amylase inhibitors family from Delonix regia with activity toward Coleopteran insects

Crop improvement generally focuses on yield, seed quality and nutritional characteristics, rather than resistance to biotic and abiotic stresses. A clear consequence of this approach is the absence of natural anti-feedant toxins in some improved seed materials, allowing predation of commercial crops by insect herbivores. Cowpea (Vigna unguiculata), commonly cultivated by small farmers, is particularly affected by insect-pests that reproduce and develop inside stored seeds. One alternative to conventional pesticides for pest control is the use of biotechnological tools, such as the digestive enzyme inhibitors, that could be introduced in transgenic crops to enhance resistance. In this study, it was verified that the in vivo bioassays using artificial seeds containing 0.5%, 1.0% and 1.5% (w/w) of Delonix regia rich fraction, containing α-amylase inhibitors with effectiveness toward insect α-amylases and other sources, caused remarkable reduction in development and increased mortality of Callosobruchus maculatus cowpea weevil and to cotton boll weevil Anthonomus grandis. Therefore, attempts were made to isolated those inhibitors by SP-Sepharose ion exchange chromatography followed by high performance liquid chromatography on a Vydac C18-TP analytical column. Four inhibitor peaks were obtained with molecular masses of 6.0, 20 and 24 kDa. Their N-termini showed high sequence similarities with Kunitz-like inhibitor family members. These results provide evidence that D. regia synthesizes a multiple family of Kunitz-like α-amylase inhibitors, with different molecular masses and a wide biotechnological potential to control insect-pests.     

近30年来浑善达克沙地-湿地的气候变化发展趋势及适应对策

应用遥感和地理信息等技术手段,结合野外实地考察验证,获取浑善达克沙地内部和周边湿地的时空分布和动态变化数据,主要对沙地和湿地的利用现状、动态变化及其研究区未来气候变化演变趋势进行分析。结果表明:近30年来浑善达克沙地及其周边湿地面积经历了先缩小后扩大再缩小的发展趋势,湖泊面积先增加后减小;流动沙地面积增加,半固定沙地面积减小;年平均气温呈逐年递增的趋势,年降水量从70年代开始递增,90年代最大,2001~2005年平均降水量又有所下降,而年蒸发量呈稳定下降趋势。同时,分析了沙地与湿地动态变化之间的内在联系,以及影响沙地与湿地变化的主要气候因子,提出该区域适应气候变化的对策。     

Direct and indirect job generation in the farmed shrimp production chain 1

Abstract

This research identifies and analyzes the direct, indirect and induced jobs generated by the production chain of post larvae hatcheries, shrimp farms and processing plants in Brazil. Using data collected in case studies and auxiliary data, results show that the shrimp production chain generates 1.89 direct jobs per hectare plus 1.86 indirect and induced jobs also per hectare. The number of jobs generated by the shrimp production chain is greater than the number of jobs generated by irrigated fruit production, a sector currently generating many new job opportunities, and greater than the number of generated jobs in sugar and coconut production, typical primary industries of the coastal areas of the Northeast of Brazil.     

2008年沈阳市花生新品种比较试验

通过丰产性、抗逆性及适应性等方面对沈阳市引进的花生新品种进行品比试验,结果表明：鲁花11、花育23、铁引花1、阜花11、花育22、花育16、连花6等品种可推广应用,本试验为筛选适合沈阳市大面积种植的高产、稳产、优质、高抗的花生品种提供科学依据。     

Seasonal Variation of Plasminogen Activator Activity in Spermatozoa and Seminal Plasma of Boar,Buck, Bull and Stallion

Plasminogen activators (PA) are proteolytic enzymes present in the spermatozoa and seminal plasma of various species. They play a role in the binding of the spermatozoon and its penetration through the layers surrounding the oocyte. Plasminogen activator activity (PAA) is modulated by hormones that have a seasonal variation, such as testosterone and melatonin. The present study investigates the seasonal variation of PA activity in sperm extracts and seminal plasma of four farm animal species: boar, buck, bull and stallion. Semen samples were collected every second week during a 12‐month period and PAA was determined. With respect to sperm enzyme activity, the boar showed a peak from late January until the beginning of April, whereas the activity in the bull was at the highest levels from April until October and gradually declined during autumn and winter period. Plasminogen activator activity of stallion spermatozoa peaked during March and April, and remained low throughout the rest of the year, whereas in the buck sperm, PAA increased from late October until the end of January. No biologically significant variation was detected regarding the seminal PAA activity in any of the species studied. While seasonality of reproduction is typically studied from the female perspective, the present data provide compelling information about a factor that may affect the reproductive ability of the male.     

吉林省主要农作物秸秆资源评价及能源化利用分析

从吉林省农作物秸秆生产与利用现状入手,针对吉林省秸秆能源化利用中存在的问题及发展状况,对吉林省农作物秸秆资源量进行了定量评价。结果表明,2008年吉林省主要农作物秸秆实物资源量为4 038.89万t,其中,可能源化利用的秸秆量达3 101.99万t,折合标准煤1 622.58万t;单位土地面积可能源化利用的秸秆量为7.97 t/hm2,其中:松原10.43 t/hm2、四平9.15 t/hm2、白城8.47 t/hm2、长春8.16 t/hm2;这些地区具有秸秆能源化利用的资源优势。在此基础上,指出吉林省秸秆能源化利用的产业化发展政策建议。     

吉林省农业温室气体排放核算及特征分析

分析了吉林省农业生产温室气体排放系数,对2000—2014年吉林省温室气体排放量进行了估算。结果表明:12000—2014年吉林省温室气体排放量由1 927.94万t增长到2 445.25万t,经历了快速上升、快速下降和缓慢上升3个阶段,目前吉林省正处于农业温室气体排放上升阶段,减排压力较大;22000—2014年吉林省温室气体中CH_4的排放贡献率为41.41%,N_2O的排放贡献率为58.69%;32000—2014年农用地N_2O是吉林省温室气体第一排放源,年均所占比重为46.32%,其他温室气体排放量从大到小依次为动物肠道CH_4、动物粪便管理N_2O和稻田CH_4,所占比重分别为29.83%、14.11%、10.41%。最后,依据吉林省温室气体排放量和结构特征,从农业生产角度提出了减排措施。     

孕穗期低温胁迫对寒地水稻产量和品质的影响

以黑龙江省25份主栽水稻品种及苗头品系为试材,在孕穗期平均16.1℃,处理5 d的试材为低温处理,以正常栽培管理的试材为对照,分析低温胁迫对不同水稻品种(系)品质性状及产量的影响。结果表明,低温处理导致所有试材每穴实粒数、结实率、千粒重和产量下降,根据相对结实率分为1、3和5级,其中以3级最多、5级最少,分别占总材料的56%和8%。低温处理导致材料糙米粒长、宽和厚下降,但是1和3级材料下降幅度更大;低温处理稻米整精米率、直链淀粉含量、蛋白质含量、起浆温度和消减值增加,稻米糙米率、精米率、最高黏度和崩解值下降,但是耐冷性中等的材料直链淀粉和蛋白质含量增加幅度更大。相关分析表明,相对结实率与每穴实粒数、每穴产量和冷胶黏度的冷水反映指数(CRI)呈极显著正相关,与崩解值和回复值的CRI值呈显著正相关。综上所述,孕穗期低温胁迫对水稻产量和品质的影响在品种间存在很大差异,在低温胁迫下耐冷性极强品种(系)每穴实粒数、结实率、千粒重、直链淀粉和蛋白质含量及最高黏度对低温反应迟钝,这是耐冷性极强品种(系)保持较高产量和优良品质的重要形态特征和生理原因。     

不同类型日粮奶牛体外消化性能与甲烷产生量比较

为控制动物甲烷排放提供参考依据,以奶牛为瘤胃液供体动物,采用体外消化法进行了日粮类型对CH4产生量及其与消化性能关系的研究.结果表明,日粮精粗比均为40:60的条件下,粗料为玉米秸秆青贮日粮的CH4产生量、消化单位干物质(DM)的CH4产生量、单位消化能量的CH4产生量比粗料为干玉米秸秆日粮分别减少了30%、37%、32%,差异显著(P<0.05);粗料均为玉米秸秆青贮的条件下,精粗比60:40日粮的CH4产生量、消化单位DM的CH4产生量、单位消化能量的CH4产生量比精粗比40:60日粮分别减少了21%、23%、23%,差异显著(P<0.05).玉米秸秆经过青贮处理或适当增加日粮中精料比例可以显著减少甲烷的产生,同时可以提高干物质消化率和消化能比例.