GA_3、IAA和C/N对马铃薯试管匍匐茎及试管薯形成的影响

以马铃薯栽培品种中薯３号、大西洋、米拉脱毒试管苗为材料,着重研究了离体条件下,外源激素、培养基Ｃ／Ｎ对匍匐茎发生及试管薯形成的影响。结果表明：①ＧＡ３、ＩＡＡ对诱导匍匐茎发生有明显的作用,处理时间和处理浓度的不同,对试管薯形成有不同的影响,以ＧＡ３０．５ｍｇ／Ｌ＋ＩＡＡ１ｍｇ／Ｌ诱导匍匐茎发生６～９ｄ,再转入结薯培养基培养,单株结薯量最大。②不同Ｃ／Ｎ处理匍匐茎发生数量不同,Ｃ／Ｎ值与成薯指数呈三次抛物线形式变化,Ｃ／Ｎ＝１７．６６９时,成薯指数最大。     

Effects of intensive mariculture on the sediment environment as revealed by phytoplankton pigments in a semi‐enclosed bay,South China Sea

Phytoplankton pigment concentrations in the surface sediments of a fish and oyster farm in Dapeng Cove, South China Sea, were measured monthly to investigate the effects of mariculture on the environment from December 2011 to December 2012. The highest contents of the identified phytopigments, sulphides and total organic carbon in the surface sediments were all found at the fish farm, followed by the oyster farm; the lowest contents were detected at the control site. Fucoxanthin in the surface sediments was the most abundant carotenoid and was significantly correlated with chlorophyll a (Chl a; r = 0.922, P < 0.01). This finding suggested that the deposited diatoms could be the main source of the Chl a concentration. Besides a differential sedimentation of phytoplankton (i.e. higher downflux at fish and oyster site than that at control site), we assume that the extent of pigment diminution from the fish site to control site was also controlled by the chemical conditions of the surface sediments. The fish farm provided the most optimum preservation conditions for the phytopigments and was a good sink for phytodetritus among the three sites because of its anoxic and reductive characteristics. Phytoplankton pigments could be useful biomarkers to evaluate the influence of mariculture on sediment environment.     

轻、中和重稀土元素对球等鞭金藻的促生长作用

轻、中和重稀土元素对球等鞭金藻的生长有相同程度的促进作用,但其有益浓度范围不同,镧为７．２８～８７．４０μｍｏｌ／Ｌ,钆为６．３６～５７．２３μｍｏｌ／Ｌ,镱为５．７８～１７．３４μｍｏｌ／Ｌ。这３种稀土元素对球等鞭金藻的最佳浓度分别为：３６．４２～６５．５５,１９．０８～５７．２３和５．７８～１７．３４μｍｏｌ／Ｌ。可分别提高单胞藻数量２１．８％～２４．３％,１０．４％～１７．２％和１７．９％～２３．０％;叶绿素含量较对照组分别提高了２９．３％～４１．２％,２５．６％～３８．１％和３６．５％～４０．３％。     

禽源空肠弯曲杆菌耐药性与致病性研究

为了解不同环节禽源空肠弯曲杆菌携带状况及其耐药性与致病性,从肉鸡养殖环节和屠宰环节采集600份样品并分离到241株空肠弯曲杆菌,采用微量肉汤稀释法和PCR方法对分离菌株进行耐药性和毒力基因检测.结果显示:分离菌株对环丙沙星、萘啶酸、四环素的耐药情况尤为严重,耐药率分别为97.75％、96.78％、95.18％;养殖环节...     

不同调控技术对晚稻机插秧秧苗生长及产量的影响

为了探索不同调控处理对晚稻机插秧秧苗生长及产量的影响,以‘H优518’和‘岳优9113’为试验材料,在大田栽培的条件下进行了用烯效唑浸种、多效唑喷雾拌种、两次叶面喷多效唑的比较试验。结果表明,晚稻品种‘H优518’和‘岳优9113’在烯效唑浸种处理下苗高、叶龄、成秧率、百株鲜重均相对较大,能显著提高机插质量,全生育期缩短1天,干物质重量最大,产量最高分别为7354.5 kg/hm~2和7236 kg/hm~2。多效唑喷雾拌种的处理产量次之。两次叶面喷多效唑的处理茎基宽最大,但全生育期延长1天。综合来看,烯效唑浸种处理最有利于培育健壮的晚稻机插秧秧苗,提高插秧质量,缩短生育期,保证机插秧产量,有利于水稻机械化栽培。     

不同处理诱导新海16号体细胞胚胎同步化发生

【目的】旨在探索诱导海岛棉体细胞胚胎同步化发生的有效方法。【方法】以海岛棉品种新海16号的胚性愈伤组织为材料,研究了低温、饥饿和渗透处理诱导体细胞胚胎同步化发生的效果。【结果】在低温处理组中,4℃诱导时体细胞胚胎发生的数量随着低温诱导时间的延长而显著增加;10℃诱导时,不同诱导时间下各处理体细胞胚胎发生的数量差异不显著,但都显著高于对照(28℃);缺磷、缺氮、缺肌醇3种饥饿处理的体细胞胚胎的数量都随着处理时间的延长而减少;渗透处理组中,在含40 g·L-1葡萄糖的培养基上诱导7 d的效果最佳。【结论】4℃处理3 d、缺磷处理5 d、缺氮处理5 d以及40 g·L-1葡萄糖诱导7 d可以显著促进新海16号的体细胞胚胎同步化发生,其中4℃处理3 d的诱导效果最佳。     

水稻收获打捆一体机打捆装置仿真分析

虚拟样机可以对机械系统进行运动学和动力学分析。为此,运用三维建模软件UG对水稻收获打捆一体机打捆装置零部件进行三维建模、装配,完成水稻收获打捆一体机打捆装置零部件的虚拟样机设计。虚拟样机的设计需要高尺寸精度与各零部件之间的准确约束,通过零部件的三维绘制与装配,再进行整机的装配,对样机进行干涉检查,可提高研发效率。打捆装置虚拟样机的建立为后续的虚拟样机运动仿真及其打捆装置零部件的结构优化奠定了良好的基础。对仿真后输出的曲线进行分析和讨论,使其符合真实的打捆环境,结果表明:各个装置的时序配合精准,能够较好地反映出整个打捆的过程,对实体的组装具有较大的指导意义。     

碱处理玉米秸秆制备可降解育苗钵研究

以碱处理玉米秸秆制备的悬浮浆液为原料,采用负压吸附成型工艺,利用有机可降解育苗钵成型机做钵,进行可降解育苗钵成型探索。试验发现:碱处理玉米秸秆得到的秸秆纤维中纤维素和半纤维素总量保持在7 5%~8 5%,碱浓度越高,纤维素比例越高;TS在4%~6%时,育苗钵的湿坯含水率适宜,对应浆液表观粘度也较大,育苗钵成型效果好;吸浆时间在1.5~3s、真空度在230~270k Pa时,育苗钵湿坯含水率在合适范围,吸附力对浆液表观粘度影响较小,育苗钵成型效果较好。本研究可为育苗钵的成型和降解提供参考。     

Lamoka,a Variety with Excellent Chip Color Out of Cold Storage and Resistance to the Golden Cyst Nematode

Lamoka is a white-skinned, white-fleshed potato variety notable for excellent chip color from cold storage, good yield and specific gravity, and resistance to both common scab and race Ro1 of the golden cyst nematode (Globodera rostochiensis). It was selected from a cross made at Cornell University in 1998 between NY120 and NY115. The tubers are round-oblong and slightly flattened, with shallow eyes and relatively smooth skin. Chip color out of cold storage is better than ‘Snowden’. Marketable yield averaged 90% of Snowden across 95 trials in New York, Pennsylvania and Maine, while specific gravity averaged 0.003 less than Snowden. Lamoka was released by the New York Agricultural Experiment Station in 2011.     

波流作用下围网养殖工程的桩柱结构受力分析

桩柱结构广泛应用在大型围网养殖工程中,其主体结构的安全与稳定关系到围网养殖的成败。该研究以舟山桃花岛海域双排桩柱式围网养殖工程结构(Prestressed High-intensity Concrete (PHC)桩,桩径0.6 m,极限弯矩0.246 MN·m)为例,采用地基反力法中的常数法,将海床土体简化为若干个相互独立的弹簧,分析不同水流速度、波高、水深、埋深以及波流联合条件下桩柱结构的力学特性。结果表明:桩柱结构最大位移在结构顶面且随流速、波高、水深的增加而增大,随桩柱结构埋深的增加而减小;弯矩零点上下两侧正、负弯矩均沿水深方向先增大后减小,呈现镜像的"S"形,桩柱最大弯矩在海床面以下2 m范围内且随流速、波高和水深的增加而增大,随桩柱结构埋深增加而减小;单纯流速为0.8、1.0、1.2、1.5 m/s条件下,该养殖结构安全稳定,当波高大于5 m或波高3 m、流速1.0 m/s时,桩柱结构将发生破坏;根据该研究结果,桃花岛海域围网养殖工程桩柱埋深应不小于17 m,海床面以上桩柱结构露出高度与海床埋深之比以小于0.8为宜。研究结果可为类似桩柱式围网养殖工程设计和建造提供参考。