Apparent digestibility coefficients of selected protein feed ingredients for loach Misgurnus anguillicaudatus

Apparent digestibility coefficients of dry matter, crude protein, lipid and energy, and amino acids availability in white fish meal, brown fish meal, meat meal, fermented soybean meal, soybean meal and rapeseed meal were determined for loach (Misgurnus anguillicaudatus) (12.05 ± 0.21 g), using a reference diet with 5 g kg^?1 chromic oxide and test diets that contained 700 g kg^?1 reference diet, by weight, and 300 g kg^?1 of the test feed ingredients. The juvenile loach was held in 300‐l tanks at a density of 30 fish per tank. White fish meal, brown fish meal, meat meal and fermented soybean meal had highest apparent digestibility coefficients (ADCs) of dry matter, crude protein and gross energy among ingredients tested, ranged from 50.4% to 60.9% for dry matter, from 64.6% to 88.4% for crude protein and from 57.9% to 79.0% for gross energy. The apparent digestibility coefficients of dry matter ranged from 61.0% to 66.9% for animal products and 50.4% to 60.7% for plant products. For crude protein, apparent digestibility coefficients of protein exceeding 80% were observed for white fish meal, brown fish meal, meat meal and fermented soybean meal, and the apparent digestibility coefficients of protein in rapeseed meal were the lowest among all the treatments. Lipids from both animal and plant feedstuffs were poorly digested by loach, ranging from 64.0% to 77.6%. The apparent digestibility coefficients of energy were similar to those of dry matter and protein, and the highest and lowest ADCs of energy were found in WFM and RM, respectively. The loach used dietary phosphorus from the animal feedstuffs more efficiently than from plant feedstuffs (soybean meal and rapeseed meal), with ADC‐values ranging from 42.3% to 53.1% and from 25.1% to 32.7%, respectively. For the animal products, the availabilities of amino acids in white fish meal and brown fish meal were higher than that in meat meal, expect for Met, Asp, Pro, Gly, and Cys. Among all the plant products, the availabilities of amino acids in fermented soybean meal were higher than in soybean meal and rapeseed meal, and thus had a greater potential to be used as a dietary replacement of fish meal in loach diets.     

不同饵料对中华虎头蟹幼体发育和存活率的影响

为探讨中华虎头蟹苗种繁育过程中饵料及投喂的影响,进行了不同饵料对中华虎头蟹溞状幼体和大眼幼体生长发育和存活的影响实验。实验结果,中华虎头蟹各期幼体生长发育效果较好的饵料为动物性饵料,Z1期以卤虫无节幼体为开口饵料,只投喂扁藻后期幼体发育较差;Z2以轮虫和卤虫无节幼体的搭配为好;Z3期则以轮虫为适宜饵料;M期投喂卤虫无节幼体效果相对较好。     

Cybrid/hybrid plants regenerated from somatic fusions between male sterile Satsuma mandarin and seedy tangelos

Somatic hybridization provides an alternative for transferring mitochondria-encoded cytoplasmic male sterility (CMS). Herein, symmetric protoplast electrofusion was conducted between embryogenic callus protoplasts of Citrus unshiu Marc. cv. Guoqing No. 1 (G1), a CMS cultivar, and mesophyll-derived protoplasts of seedy ‘Page’ tangelo [C. reticulata Blanco × (C. reticulata Blanco × C. paradisi Macf.)] or ‘Nova’ tangelo [C. reticulata Blanco × (C. reticulata Blanco × C. paradisi Macf.)], to transfer CMS trait. Flow cytometry analysis showed that 14 plants recovered from G1 + ‘Page’ tangelo that displayed typical morphological character of ‘Page’ were diploid, and 6 plants regenerated from G1 + ‘Nova’ tangelo were tetraploid. Genetic compositions of regenerated plants from the two fusions were determined by SSR, CAPS and chloroplast-SSR analysis. Cybrid nature of diploids from G1 + ‘Page’ tangelo with nuclear DNA from ‘Page’, mitochondrial DNA (mtDNA) from the G1 and chloroplast DNA (cpDNA) derived from either parent was confirmed. Tetraploid plants from G1 + ‘Nova’ tangelo were identified as somatic hybrids with random cpDNA inheritance. The regenerated cybrid and hybrid plants hold great potential for Citrus seedless breeding at diploid or triploid levels.     

日光温室内光合有效辐射基本特征分析

基于日光温室内观测的辐射资料,对光合有效辐射特征及对作物的影响进行研究分析.结果表明:温室内日光合有效辐射累计值与日水面蒸发量呈较好的线性关系,相关系数为0.7974;日光温室内作物光合速率随光合有效辐射上升到一定程度后,将不随光合有效辐射的增加而增加;叶片细胞液质量分数与光合有效辐射日变化均呈单峰型曲线,叶片细胞液质量分数相对于光合有效辐射有明显的滞后现象;日光温室内冬、春季晴天及阴天的太阳总辐射Q和光合有效辐射(PAR)日变化均为单峰型曲线,晴天和阴天太阳总辐射和光合有效辐射日变化趋势一致,阴天比晴天小;2007年秋季和2008年春季日光温室内小型西瓜的光合有效辐射利用率分别为6.38%和6.31%,高于大田作物的光合有效辐射利用率值.     

覆膜穴播施肥联合作业机械的研制

设计了一种适合膜上播种的双环带分种分肥穴播器,并采用该播种器研制了覆膜穴播施肥联合作业机械;同时发明了切膜机构、整平机构和覆土机构.通过大量的实验表明,覆膜穴播施肥联合作业机组工作稳定可靠,性能优良,是一款与新农艺相适应的机械化联合作业的机型.     

苎麻新品种“华苎4号”选育研究

“华苎 4号”是从稀节巴品种自然杂交后代中选育出来的新品种。该品种产量高 ,在品系比较试验中平均亩产 2 2 6 .5kg ,比对照细叶绿品种增产 5 9.1 3% ,在湖北省区试中较对照增产 33.81 % :纤维品质优良 ,在品系比较试验中年均纤维细度 2 0 82支 ,在区试中经湖北省纤检所测试 ,年均纤维细度 2 2 39支 ;该品种植株高大整齐 ,出麻率特别高 (鲜皮出麻率和鲜茎出麻率分别在 1 4%和 5 %以上 ) ;“华苎 4号”的抗逆性强 ,高抗炭疽病 ,不感染花叶病 ,抗旱抗风性强 ,但耐渍性略差。     

盐碱地的园林绿化工程改造

与从事盐碱地元绿化工程改造的同行朋友进行沟通与交流,不断提升盐碱地园林绿化工程改造水平,助推我国园林绿化工程建设实现更好更快地发展。     

海南龙血树组织培养过程中血竭形成的诱导

以海南龙血树组培苗为材料,研究组织培养过程中不同植物激素和浓度、不同龙血树组织、不同光照条件对血竭形成诱导的影响.结果表明:植物细胞分裂素(6-Benzylamino purine,6-BA)可以诱导龙血树组培苗产生血竭,其诱导的效果与6-BA的浓度无关.而与光照条件有关,并且在一定的范围内其诱导效率与光照强度成正相关:血竭的形成与组培苗的木栓化程度有关,木栓化程度越高,越容易诱导血竭的形成.     

福建省南山风景区景观动态预测

在遥感图像软件ERDAS Imagine8.5/ArcviewGIS3.2的支持下,以福建省南山风景区两个时期(1988、2004年)的影像为基础数据,对影像进行配准、图像判读、目视解译和矢量化处理,得出各个景观类型的动态变化数据, 并利用马尔柯夫模型对景观格局变化进行动态预测.结果表明:在人类活动和自然因素的影响下,研究景区各景观类型变化均较明显且复杂,达到稳定状态时各景观类型的面积分别为4.1504(茶园)、400.3525(荒山荒地)、1395.1679(建筑)、94.8203(柳杉)、49.1661(毛竹)、337.777 5(农田)、61.2980(杉木×马尾松)、380.2391(水体)、299.4662(松杂)、173.9969(阔叶树)hm2.其中,茶园、荒山荒地、柳杉、毛竹等景观类型呈现先上升后下降趋势,直至达到稳定状态;松杂景观仅在2018年前略有上升,随后即发生下降;建筑景观、水体面积比例始终处于上升状态;农田、杉木x马尾松和阔叶林景观则始终处于下降的趋势.由于建筑面积将大量增加,而森林景观面积则减少,景区的生态环境问题将更加突出,应该从景观和生态角度出发对各景观斑块加以管理.