甜玉米纸筒育苗移植规范化栽培技术

为提高甜玉米生产上的保苗率,延长生育期,增加积温,提高单产水平,我们联合承担了甜玉米纸筒育苗移栽研究任务。研究结果表明,甜玉米纸筒育苗称栽技术上可节约种子４ｋｇ／ｈｍ＾２增加积温２５６．８℃～３６４．２℃增加生育期１５～２５ｄ,提高保苗率,提高抗御苗期蝼蛄,蛴螬,地老虎等危害的能力,整套技术包括：育苗方法,床土配制,育苗栩类型,育苗管理技术（温度与湿度）壮苗标准及移栽方法,时期等。     

Grow‐out performance of Kuria labeo,Labeo gonius (Hamilton), with major carps in carp polyculture system

A year‐long grow‐out carp polyculture trial was conducted in nine earthen ponds to study the growth performance of Kuria labeo (Labeo gonius) with the different major carps such as catla (Catla catla), silver carp (Hypophthalmichthys molitrix), rohu (Labeo rohita) and mrigal (Cirrhinus mrigala). Suitable water quality parameters were maintained in ponds through intermittent liming, manuring and fertilization. Three different species combinations of carps were evaluated using silver carp and catla as the common species and varying other carp components as rohu–Kuria labeo, mrigal–Kuria labeo and rohu–mrigal in the three treatments. The ponds were stocked at a combined density of 7500 fingerlings ha^?1. Silver carp and catla showed similar growth performances in all the three combinations, suggesting that other carps in the combination do not have any differential influence on their growth. Kuria labeo was compatible with rohu, while competition was observed with mrigal. Although growth performance of Kuria labeo was inferior to that of mrigal, better compatibility of Kuria labeo with rohu helped this combination to yield a biomass equivalent to the mrigal–rohu combination, suggesting feasibility to use Kuria labeo as an alternative species to mrigal in the major carp polyculture system without compromising the total biomass yield.     

Macro‐geographical differences influenced by family‐based expression on cultured pearl grade,shape and colour in the black‐lip ‘pearl oyster’ Pinctada margaritifera: a preliminary bi‐local case study in French Polynesia

In French Polynesia, the aquaculture of Pinctada margaritifera is carried out in numerous grow‐out sites, located over three archipelagos (Gambier, Society and Tuamotu). To evaluate the impact of macro‐geographical effects of these growing sites on pearl quality traits, five hatcheries produced families were used as homogeneous donor oysters in an experimental graft. The molluscs were then reared in two commercial locations: Tahaa Island (Society) and Rangiroa atoll (Tuamotu). At harvest, eight pearl quality traits were recorded and compared: surface defects, lustre, grade, circles, shape categories, darkness level, body and secondary colour and visual colour categories. Overall inter‐site comparison revealed that: (1) all traits were affected by grow‐out location except for lustre and round shape, and (2) a higher mean rate of valuable pearls was produced in Rangiroa. Indeed, for pearl grade, Rangiroa showed twice as many A‐B and less reject samples than Tahaa. This was related to the number of surface defects (grade component): in Rangiroa, twice as many pearls had no defects and less pearls had up to 10 defects. Concerning pearl shape, more circled and baroque pearls were found in Tahaa (+10%). For colour variation, 10% more pearls have an attractive green overtone in Rangiroa than in Tahaa, where more grey body colour were harvested. Lustre does not seem to be affected by these two culture site (except at a family scale). This is the first time P. margaritifera donor family have been shown to vary in the quality of pearls they produce depending on their grow‐out location.     

氯对压砂西瓜生长、产量与品质的研究进展

氯作为植物必须的微量元素之一,少则有益,多则有害,宁夏长期采用含氯的微咸水进行补灌,使得土壤中的氯离子进行累积,西瓜作为一种忌氯作物,对氯较为敏感,易发生毒害作用。本研究综合前人的研究成果,探讨了氯肥对宁夏压砂西瓜生长、产量和品质的影响,为农户科学合理的施用氯肥提供理论依据,展望了氯肥的研究前景。     

杨树新无性系苗期试验

对杂交选育和引种的9个杨树无性系进行扦插试验,结果表明：不同无性系的苗期地径、胸径和苗高生长量存在极显著差异,其中黑小2号、J10、J7等3个无性系表现最优,地径、胸径、树高分别较小黑杨提高45.03%～22.16%、70.99%～14.96%、44.31%～16.43%。     

松塔景天组织培养与快速繁殖的研究

以松塔景天幼嫩叶片作为外植体,利用含有不同浓度配比植物生长调节剂的培养基分别进行愈伤组织的诱导、不定芽的诱导、生根培养及驯化移栽,建立了松塔景天组织培养和快速繁殖体系。试验结果表明：诱导愈伤组织的最适培养基为MS＋6-BA 0．5 mg/L ＋NAA 0．05mg/L ,愈伤组织诱导率达87．78％;诱导不定芽的最适培养基为MS＋6-BA 1．0mg/L＋ NAA0．1 mg/L ,不定芽诱导率达88．89％;组培苗最佳生根培养基为1/2 M S＋IB A 0．3 m g/L ,生根率达91．33％;组培苗的移栽成活率达84％。     

日粮粗蛋白和大米活性肽添加水平对断奶仔猪生长及血液生化指标的影响

采用3×3双因子试验设计,其中粗蛋白质设17.0%、18.5%、20.0%三个水平,大米活性肽设0、1%、2%三个水平,研究了日粮中粗蛋白质水平和大米活性肽的不同添加量对断奶仔猪生长性能和血液生化指标的影响。结果表明,在断奶仔猪的日粮中添加1%~2%的大米活性肽,可明显提高仔猪的生长性能,平均日增重和平均日采食量分别增加5.37%~7.13%和4.62%~5.49%,料重比降低了0.63%~1.86%;还可将日粮中粗蛋白质含量降低1.5~3.0个百分点;同时,添加1%~2%的大米活性肽还能显著增强仔猪的抗氧化能力和免疫功能。     

红松种材林基地建设有关措施的探讨

辽宁红松种材林基地建设是一项重要富民工程。要完成百万亩的建设任务,必须大力抓好宣传引导、经济扶持和技术保障工作。     

生长鸡胫骨对过量镁的后效应

蛋雏鸡采用玉米豆饼型日粮,添加过量镁(MgO),结果胫骨中镁含量增加,钙、钠等元素含量降低,钙:磷、钙:镁、磷:镁的比值减小,在育成期转饲正常日粮,通过成骨及溶骨作用,经过3～6周时间,胫骨中镁、钙、钠、磷的含量及他们之间的相互比值都恢复正常。     

水杨酸对两种细菌生长的影响

把一定浓度的菌液在含有不同浓度水杨酸的基础培养基上培养12h,细菌的生长情况也会不同。当水杨酸的浓度较低时,会促进细菌生长;超过某一定值时,水杨酸对细菌生长的促进作用则会随着水杨酸浓度的增加而降低。实验发现最适合大肠杆菌生长的水杨酸浓度是1.5mg/L,最适合枯草芽孢杆菌生长的水杨酸浓度为4.0mg/L。单因素方差分析表明在本实验浓度范围内水杨酸对大肠杆菌和枯草芽孢杆菌生长的影响都是显著的(P<0.05)。