Vitreosity,its stability and relationship to protein content in durum wheat

High quality requirements are set on durum wheat (Triticum durum) from semolina mills and pasta producers. For the production of semolina and pasta with good cooking quality, high grain protein content and vitreosity is required. The dependency of vitreosity on protein content as well as its stability under the influence of humidity was not well investigated up to now. We (1) compared two methods to determine vitreosity, (2) investigated the relationship between vitreosity and protein content, (3) developed a method to analyze vitreosity under humidity, and (4) examined the relationship between protein content and agronomical as well as quality traits in durum wheat. The results showed that the formation of vitreous kernels greatly depends on the protein content. To evaluate the stability of vitreosity under the influence of humidity a new method was elaborated and employed to assess the durum germplasm under study. This revealed that vitreosity of a durum wheat variety depends on the potential to form vitreous kernels but also to maintain this vitreosity under the influence of humidity. Our results further show that protein content is a central trait in durum wheat that strongly influences important traits like grain yield, vitreosity, and b-value.     

Histopathological Changes in Third-Instar and Adult Anastrepha ludens (Diptera: Tephritidae) After in vitro Heat Treatment

The Mexican fruit fly, Anastrepha ludens Loew (Diptera: Tephritidae), is one of the most harmful pests of mango causing direct damage by oviposition on the fruit pulp. Mango for export is subjected to hydrothermal treatment as a quarantine method for the control of this pest, but exposure to heat for long periods of time reduces considerably the quality and shelf-life of treated fruit. The aim of this work was to study morphological changes of third-instar larvae and adults of A. ludens after in vitro exposure to high temperature at sublethal times. A heating block system was used to expose larvae at 46.1°C for 19.6 and 12.9 min, producing 94.6 and 70% mortality, respectively. Treated larvae were processed for optical microscopy. A fraction of surviving treated larvae was separated into containers with artificial diet to allow development into adults. Adult sexual organs were dissected and processed for transmission electron microscopy analysis. Results showed that 94.6% of the treated larvae died at 46.1°C for 19.6 min and none of the surviving larvae eclosed to adulthood, as they developed as malformed puparia. For the in vitro treatment at 46.1°C during 12.9 min, 70% of the treated larvae died and only 3.75% reached the adult stage, but ultrastructural damage in the male testes and in the female ovaries was observed. Additionally, 11.1% of the adult flies from the in vitro treatment also showed wing malformation and were incapable of flying. The analysis showed that surviving flies were unable to reproduce.     

鸭茅幼苗生长及形态对铝胁迫的响应

选取我国西南地区的鸭茅(Dactylis glomerata)主栽品种‘德纳塔’、‘安巴’、‘宝兴’和‘牧友’为供试材料,研究酸性环境下不同梯度的铝离子(0,10,30,50和100 μM)对鸭茅幼苗生长及形态的影响。结果表明:铝胁迫下,鸭茅枝条干重、根系干重、植株形态及根系伸长均受到显著抑制,且随着浓度的增加呈现出下降趋势;低浓度(10～30 μM)铝离子处理对鸭茅生长造成的抑制较弱,对鸭茅植株的健康形态塑造没有造成影响;而高浓度(≥50 μM)铝离子处理则对鸭茅植株根系伸长和植株形态造成严重的抑制,不利于植株后期的健康生长;供试鸭茅地下部根系积累铝的量要大于地上部枝条,且品种间存在一定差异,‘牧友’根系中铝含量最低,耐受性较强。表明鸭茅通过改变植株形态和调控自身积累铝的水平来应对酸性土壤中的铝离子胁迫,但是酸性铝离子环境对鸭茅早期生长仍具有一定的毒害作用,低浓度造成的影响较小,而高浓度则对鸭茅植株生长和形态塑造均造成不良的影响。     

Ovulation induction in jundiá (Rhamdia quelen,Heptapteridae) using carp pituitary extract or salmon GnRH analogue combined with dopamine receptor antagonists

Jundiá (Rhamdia quelen) is an important species for aquaculture in temperate and subtropical climates. In the present study, the results of different forms of GnRH analogue treatments on ovulation in jundiá have been compared with those from treatment with carp pituitary. Seven out of eight females ovulated in groups treated with carp pituitary (4.0 mg kg^?1 BW) and Ovaprim (0.5 mL kg^?1 BW). Injection with sGnRHa (10 μg kg^?1 BW) combined with metoclopramide (20 mg kg^?1 BW) caused a significantly lower rate of ovulation with three out of eight females responding. None of the fish injected with sGnRHa (10 μg kg^?1 BW) alone ovulated. Mean PGSI [(weight of stripped egg mass/BW of the female before stripping) × 100] and mean fertilization rate values were high and similar between treatment groups. The obtained results indicate that in jundiá, there is a strong dopamine inhibitory tone on gonadotropin secretion. The gonadotropin releasing activity of sGnRHa can be potentiated by dopamine receptor antagonists and the combined treatment is effective in inducing ovulation. In this regard, domperidone proved to be more potent than metoclopramide.     

不同处理对黄瓜种子萌发的影响

研究不同酸碱性溶液浸泡、不同光照变化、不同低温冷冻、不同温度水浴和不同时间超声波处理对‘伯乐一号’黄瓜种子萌发的影响。采用双层滤纸培养法对处理后的种子进行培养,观察记录种子的发芽势、发芽率和发芽指数,并对数据进行统计分析。实验显示,pH 9碱性溶液浸泡、持续黑暗处理、 48 h冷冻处理、30℃水浴处理和20 min超声波处理均可以提高‘伯乐一号’黄瓜种子发芽率;其中以48 h冷冻处理的‘伯乐一号’黄瓜种子发芽率最高,达到89.33%。总结出‘伯乐一号’黄瓜种子萌发的最适处理方法,对生产实践中有效促进其种子萌发及人工栽培具有重要的指导意义。     

矮紫金牛扦插技术初探

在冬季和春季取矮紫金牛枝条的不同部位作插穗,进行留叶量及生根粉的不同处理方式对插穗生根影响的试验。试验结果表明,矮紫金牛在春季取枝条的基部和中部作插穗,并且把叶片全部摘去,然后把插穗基部先用生根粉水剂浸0.5 h,再浆上含有生根粉的泥浆进行扦插,插穗的生根较快、生根数较多以及成活率较高。     

1例藏香猪伪狂犬病、猪圆环病毒病与附红细胞体病混合感染的诊治

为对送检的发病藏香猪病死因进行确诊,本试验采用常规PCR、RT-PCR及荧光定量PCR方法,并结合流行病学调查、临床诊断及病理剖检等实验室检测对送检病料进行诊断,结果显示病死猪心脏、肺脏充血出血,肺脏肉变,气管内充满白色泡沫,全身淋巴结出血;荧光定量PCR方法检测猪圆环病毒呈阳性,PCR方法检出猪伪狂犬病病毒特异性条带,未见猪传染性胸膜肺炎放线杆菌、猪肺炎支原体条带,RT-PCR方法未扩增出猪瘟病毒、猪繁殖与呼吸综合征病毒特异性条带;血液涂片染色镜检可见猪附红细胞体。结果表明病死猪为猪伪狂犬病、猪圆环病毒病与猪附红细胞体病混合感染,采用经实验室诊断给出的综合防治方案治疗后,疫情得到控制。本次病例的诊治为养猪业可能发生的猪伪狂犬病、猪圆环病毒病、猪附红细胞体病的混合感染提供了有效的防治方法和借鉴经验。     

5种种衣剂防治小麦主要土传病害研究

研究了5种种衣剂对小麦土传病害纹枯病、全蚀病和根腐病的防治效果。结果表明,230g/L吡虫啉·苯醚·咯悬浮种衣剂综合防治效果优于其他药剂处理,对小麦纹枯病的防治效果为73.51%～95.05%,对小麦全蚀病的防治效果为73.01%～87.41%,对小麦根腐病的防治效果为65.51%～92. 09%。按药效其次依次是60g/L戊唑醇悬浮种衣剂、30g/L苯醚甲环唑悬浮种衣剂、25g/L咯菌腈悬浮种衣剂、15%多·福悬浮种衣剂。随着小麦的生长,各处理的防效逐渐降低,但直到枯白穗期还有一定防治效果。同时230g/L吡虫啉·苯醚·咯悬浮种衣剂对小麦增产作用明显。     

温度对阿魏侧耳胞外酶活性及原基形成的影响

[目的]研究不同温度处理对阿魏侧耳菌丝胞外酶活力和原基形成的影响,为生产中阿魏菇生长发育的调控和高效栽培提供参考依据.[方法]以阿魏侧耳(CGMCC 5.00774)为菌种,采用棉籽壳、麸皮、玉米粉为培养料培养菌丝至生理成熟,分别进行5、10和15℃低温处理(对照处理25℃),于第5、10、15、20、25和30d取样测定培养料中菌丝羧甲基纤维素酶(CMC酶)、半纤维素酶(HC酶)、淀粉酶、漆酶、蛋白酶的活力,观察各处理原基形成情况.[结果]与对照组相比,5、10、15℃低温处理后CMC酶和HC酶活力降低,漆酶、淀粉酶、蛋白酶活力则一直高于对照组.5℃处理25和30 d及10℃处理25和30 d的样品出现原基,其他处理均未出现原基.[结论]低温处理能引起菌丝胞外酶活力的变化,阿魏侧耳原基分化的最适低温处理条件是10℃,25 d.