垄沟种植对土壤水分变化及夏玉米生育的影响

为探讨华北地区夏玉米垄沟种植效果和适宜种植方式,在大田条件下研究了小麦收获后起垄沟播、垄作和平作3种种植方式对土壤含水量动态变化和玉米叶片水势、生育和产量的影响。结果表明,沟播处理土壤含水量明显高于垄作和平作,叶片水势、叶面积、干物质积累也高于垄作和平作,最终产量分别比垄作和平作高3.81%和11.62%。     

The effect of lunar cycle,tidal condition and wind direction on the catches and profitability of Japanese common squid Todarodes pacificus jigging and trap-net fishing

Jigging with artificial lights (squid jigging) and deploying of large scale trap-net (also known as a set-net in Japan), are the major methods to capture Japanese common squid Todarodes pacificus in western Japan. Squid jigging is a highly selective fishing method. However, it consumes large amount of energy for steaming to the fishing ground and for lighting. In contrast, trap-net fishing requires substantially less energy but its capture efficiency is strongly influenced by its stationary mode of capture. The primary objective of this study was to analyze how various environmental and biological factors such as the lunar cycle, tidal condition, wind direction and squid abundance affect the capture efficiency of squid jigging and trap-net fishing. We analyzed the effect of these factors on squid catch in five Fisheries Cooperative Associations located on four islands in Nagasaki Prefecture, western Japan. Our analysis shows that squid catch in jigging and trap-net fishing is mainly influenced by the lunar cycle but also tide and wind direction play a marked role. In addition, squid abundance significantly affects the catches in trap-net fishing. Recommendations are made to improve the overall profitability of squid fishing by proper choice of the capture method, location and season.     

不同耕作方式保水剂对夏玉米生长发育的影响

为了明确不同耕作方式保水剂在豫东旱地夏玉米上应用效果,以‘郑单958’为试验材料,研究了其对夏玉米生长发育发育的影响。结果表明：与对照相比,不同处理提高了夏玉米的出苗率、根条数、叶面积指数和干物质积累量;夏玉米生育前期沟播覆盖保水剂效果最好,沟播保水剂次之;后期沟播覆盖保水剂最好,覆盖保水剂次之;不同处理使夏玉米产量比对照提高9.59%~54.6%,沟播覆盖保水剂最好,增产54.6%,覆盖保水剂次之,增产51.03%。表明沟播覆盖保水剂改善了夏玉米出苗和根系状况,提高了叶面积指数和干物质积累量,从而达到增产的目的。     

野生红果枸杞白粉病菌的鉴定

为白粉病菌的系统进化、致病机理及防控深入研究提供基础资料和基因资源,采用形态学、分子生物学和科赫法则相结合的方法对河南省周口地区野生红果枸杞白粉病的致病病原菌生理小种类群进行研究。结果表明:该致病菌分生孢子呈长椭圆形,大小为(12.5~16)μL×(17.5~21.5)μL。其克隆获得目的序列长度为548 bp(GenBank:KX579506.1),与已报道的穆氏节丝壳属白粉病菌JX546296.1、AF073358.1、AF455748.1和AB022380.1的ITS序列同源率分别为86.39%、87.21%、86.68%和80.19%。初步确定该病原菌属穆氏节丝壳属。     

利用实时荧光RT-PCR方法检测番茄环斑病毒和烟草环斑病毒

根据番茄环斑病毒和烟草环斑病毒各分离物CP基因的保守序列分别设计并合成1对引物和1条TaqMan荧光探针,分别建立了ToRSV和TRSV的实时荧光RT-PCR检测方法。该方法具有更加灵敏、特异、快速和简便的特点,在口岸病害检疫中具有广泛的应用前景。     

(+)-catechin acts as an infection-inhibiting factor in strawberry leaf

ABSTRACT An infection-inhibiting factor (IIF) was isolated from strawberry leaves and identified as (+)-catechin. This compound inhibited the formation of infection hyphae from appressoria of Alternaria alternata, but allowed both spore germination and appressorial formation. It is a normal component of strawberry leaves, but further accumulates as the major IIF in response to inoculation with nonpathogenic spores of A. alternata. The accumulation of (+)-catechin on a susceptible host was not induced, however, by inoculation with pathogenic spores of the strawberry pathotype or by inoculation with nonpathogenic spores supplemented with host-specific toxin (AF-toxin I). These results imply that (+)-catechin acts as a protective agent during induced resistance and that AF-toxin I acts as a fungal suppressor of induced resistance.     

磷、钾肥不同施用量对辣椒生长及产量的影响

设置N施肥量为18 kg/667 m2,P2O5施肥量为3~12 kg/667 m2,K2O施肥量为14~26 kg/667 m2,研究不同磷、钾肥施用量对贵州遵义辣椒产量的影响。研究结果表明,辣椒N、P2O5、K2O最佳施肥量为18、6~12、18~22 kg/667 m2时,干辣椒产量可达250 kg/667 m2以上。     

不同厂家胰酶制备鸡胚成纤维细胞对比试验

本试验用半胚法制备鸡胚成纤维细胞,用胰酶对SPF鸡胚进行消化培养,并观察所得细胞的生长情况。在相同条件下设立两个对照组,观察胰酶在细胞制备过程中对试验的影响,并比较不同厂家(Gibco和Difco)生产的胰酶在相同条件下对鸡胚消化情况及所得细胞生长情况的影响。     

Structural basis of RNA-dependent recruitment of glutamine to the genetic code

Glutaminyl-transfer RNA (Gln-tRNA(Gln)) in archaea is synthesized in a pretranslational amidation of misacylated Glu-tRNA(Gln) by the heterodimeric Glu-tRNA(Gln) amidotransferase GatDE. Here we report the crystal structure of the Methanothermobacter thermautotrophicus GatDE complexed to tRNA(Gln) at 3.15 angstroms resolution. Biochemical analysis of GatDE and of tRNA(Gln) mutants characterized the catalytic centers for the enzyme's three reactions (glutaminase, kinase, and amidotransferase activity). A 40 angstrom-long channel for ammonia transport connects the active sites in GatD and GatE. tRNA(Gln) recognition by indirect readout based on shape complementarity of the D loop suggests an early anticodon-independent RNA-based mechanism for adding glutamine to the genetic code.     

微咸水灌溉改良盐碱地的可行性研究

针对水资源短缺和盐碱地不断恶化等问题，微咸水灌溉农作物在理论上受到大量关注，在实践上也有良好效果，但鲜有微咸水投入改良盐碱地的理论实践，缺少一定的理论指导。对目前国内外微咸水灌溉开发和利用研究进展进行综述，总结微咸水灌溉技术的实践情况，阐明微咸水灌溉对作物、环境和土壤水盐运动的影响，详细论述微咸水灌溉提升作物产量和改良盐碱地的成果，分析其灌溉改良盐碱地的可行性，并提出微咸水灌溉改良盐碱地的研究方向和实践操作。