番木瓜货架期的防腐保鲜技术研究

为了研究番木瓜货架期的复合防腐保鲜技术,以番木瓜为试材,采用生物(Nisin)、化学(咪鲜胺)与涂膜(大豆分离蛋白、海藻酸钠)相结合的方法,以各项感官指标和理化指标做评价,对黄熟过程的番木瓜进行防腐保鲜效果研究。结果表明,最佳复合防腐保鲜工艺条件为:0.3 g/L Nisin与0.35 g/L咪鲜胺复配成复合防腐剂,处理番木瓜2 min,1%(V/V)乙烯利喷雾处理,再以3%大豆分离蛋白、0.3%海藻酸钠制成pH 7.0的复合涂膜液进行涂膜。通过此联合防腐处理,可有效延缓番木瓜的腐烂指数及失重率的上升,抑制VC和TSS含量的下降,防腐保鲜效果显著,也利于番木瓜黄熟指数的上升。     

仔猪猪瘟疫苗乳前免疫技术的应用研究

目前在对猪瘟的防治实践中,对猪瘟超前免疫后四窝抗体水平的变化以及保护效果存在争议。通过本厂的应用观察：以品种、日龄相同,胎次相近的杜长大四窝三元仔猪为检测对象,每窝随机抽取五头进行超前免疫实验,分别在20日龄,30日龄,40日龄,60日龄,静脉采血,利用IDEXX公司的猪瘟检测试剂盒进行猪瘟阻断率检测,结果表明进行猪瘟超前免疫后再在50日龄加强一次猪瘟疫苗免疫能很好的保护仔猪     

基于概率回归和信息扩散理论的南充晚熟柑橘低温冻害指标体系研究

低温冻害是南充市晚熟柑橘的主要灾害,本研究旨在建立一套低温冻害指标体系,以减少南充市晚熟柑橘因低温冻害而造成的损失。通过分析农业部门提供的冻害实验数据和历史灾情记录,并结合国家气象监测站的小时气温数据,在满足特定气候条件(冬季天空无云或少云,日温差大于等于8℃,最低气温小于等于3℃)的基础上,运用概率回归和信息扩散理论方法对低温冻害指标阈值进行研究。结果发现,两个实验果园中气象温度与实测温度的线性回归关系显著,且通过统计检验。具体为当气象温度为西充1.7℃和嘉陵2.6℃时,相应果园的实测温度将至-2℃,开始出现冻害现象。根据目前精细化天气预测能力,研究构建了一个基于两周滑动时段的复合指标阈值体系,该体系包括低温冻害日最长持续时间、总持续时间和总天数3个指标。通过对4个冻害样本的检验,结果显示冻害指标评级与实际观测到的冻害等级高度一致,证明了该冻害指标体系具有较好的实际应用价值。     

关于上一轮县级土地利用总体规划中土地利用变化及生态环境效应的思考 ——以重庆市丰都县为例

基于重庆市丰都县1996年、2004年土地利用现状与2010年土地利用总体规划数据，运用特尔斐法、层次分析法、定量分析法，对丰都县1996—2004和1996—2010土地利用变化及生态环境效应进行对比定量分析研究。结果表明：（1）土地利用格局均发生了明显变化，耕地、未利用土地减少，园地、林地、水域、交通用地增加；（2）土地利用变化引起的生态环境质量变化均呈改善趋势，其主要原因是退耕还园、还林，以及未利用土地的开发利用；（3）规划与实施土地利用变化及生态环境效应差异太大；（4）土地利用总体规划与实际土地利用变化一致性很差，缺乏科学性和严肃性；（5）对规划土地利用变化引起的生态环境改善重视不够。最后提出新一轮土地利用总体规划修编的建议。     

GIS在福建龙眼低温冻害分析中的应用

为减少福建龙眼在低温冻害中的损失,实现科学合理的种植布局,进行本研究。根据龙眼的生长情况、受害程度与年度极端最低气温、种植区域的坡向、坡度的关系,确定龙眼冻害等级指标。利用福建68个气象台站的地理信息资料,建立龙眼冻害指标的空间分布特征模型,通过GIS技术推算出50m×50m分辨率的冻害指标空间分布。利用GIS的空间分析能力,得出福建龙眼低温冻害的分布规律。     

甘蔗寒冻害等级指标及灾损指标的初步研究

为明晰甘蔗遭受不同寒冻害类型影响的症状变化及其产量、糖分含量损失情况,进而完善甘蔗寒冻害等级指标体系。综合2007/2008—2010/2011年冬季广西南、中、北甘蔗主产区不同甘蔗品种遭受寒冻害影响调查分析与典型寒冻害年份甘蔗产量、蔗糖分含量损失与气象资料相关关系分析。建立和完善甘蔗辐射型、平流型寒冻害等级指标及甘蔗产量、蔗糖分含量寒冻害损失指标,规范甘蔗不同寒冻害类型等级下受害表观症状。研究结果对开展甘蔗寒冻害动态监测预警与灾损量化评估及灾情调查、灾害防御等有积极意义。     

2010年冬季陕南柑橘受冻气象条件分析及防御对策

为了有效利用气候资源,趋利避害,合理规划和发展陕南柑橘产业,在对2010年冬季陕南柑橘越冬冻害灾情调查的基础上,分析了当年柑橘越冬期冻害形成的气候背景;结合柑橘越冬期冻害指标及低温过程中的有害积寒,分析并验证了陕南柑橘越冬期冻害等级指标,提出了用低温过程中有害积寒划分陕南柑橘越冬冻害等级的相关指标;通过对安康、汉中2市12个柑橘种植县（区）2010年冬季及历史极端最低气温和低温过程有害积寒的分析,探讨了陕南柑橘越冬期冻害西部重于东部的原因,其分析结果与调查实情基本相符;最后从多个方面提出柑橘越冬期冻害的防御对策。     

水果型番木瓜组培无菌系的构建

用无菌水、GA3 和6-BA等不同试剂对水果型番木瓜种子进行预处理后接种于培养基中,通过研究不同试剂对种子发芽率、胚芽和胚根的伸长、幼苗苗高的影响,筛选出构建水果型番木瓜组培无菌系的较好种子预处理方式。结果表明,无菌条件下用75%酒精均匀擦拭水果型番木瓜果皮表面,取出种子,用无菌水冲洗3次是较好的灭菌方法,种子污染率为2.52%;水果型番木瓜种子灭菌后经GA3 1000 mg/L+6-BA 1 mg/L（等体积混合）浸泡18 h处理后,接种于MS培养基中培养,种子发芽率、胚芽、胚根和苗高等各指标平均数达到较高值,分别为68.42%、2.25cm、0.8 cm、1.52 cm,幼苗整体生长情况较好,构建了良好的水果型番木瓜组培无菌系。     

浙江省茶树冬季冻害时空分布特征

为了分析浙江省茶树冬季冻害时空分布特征。本研究提出了茶树冬季冻害的气象指标和等级划分,基于该指标和全省64个基本气象站1971—2011年气象数据,采用经验正交函数和小波分析方法,研究了浙江省茶树冬季冻害的空间分布和时间演变特征。结果表明,茶树轻度、中度和重度冬季冻害第1模态能总体反映冬季冻害发生的多年平均状况。轻度和重度冬季冻害第1模态空间分布均表现为全省一致为正,轻度和重度高值区均位于浙江省西北部等地;中度冬季冻害第1模态空间分布表现为除温州东部、台州东南部地区外,其余地区都为负值,其特征向量绝对值的最大值位于浙北、浙中地区。研究结果可为茶树生产提供科学依据。     

巴基斯坦农业发展与中巴农业合作探析

为深入研究巴基斯坦农业发展基本情况,探索深化中巴农业合作的领域。结合国内外研究成果,在对文献资料进行梳理和综述的基础上,对巴农业资源、产业结构、管理机构设置进行了介绍。认为中巴农业合作存在规划性不强、深度不够、形式单一、地域重叠等问题,提出加强双边农业互访、合作制定中巴农业合作规划、拓宽合作领域等进一步加强中巴农业合作的建议。     

幼龄椰园套种西瓜与番木瓜对椰子生长及椰园经济收入的影响

在幼龄椰园实施套种西瓜与番木瓜后,可以明显促进椰子的生长,显著改善椰子叶片养分与椰园土壤肥力和大大增加幼龄椰园的经济收入。其中,套种效果最好的是“套种西瓜后再套种番木瓜”模式,其次是“套种番木瓜”模式,然后是“套种西瓜”模式。     

Development of male-specific markers and identification of sex reversal mutants in papaya

Papaya is a productive and nutritious fruit grown in tropical and sub-tropical regions worldwide. It is polygamous with three sex types: female, male and hermaphrodite. Sex determination in papaya is controlled by an XY sex chromosome system with two slightly different Y chromosomes, Y for males and Y^h for hermaphrodites. Comparative analysis of the hermaphrodite-specific region of Y^h chromosome (HSY) and male-specific region of Y chromosome (MSY) revealed 99.6% sequence identity, which explains why DNA markers that amplify for both males and hermaphrodites have easily been developed, but not for the male trait specifically. We examined the 0.4% sequence differences, and found 1887 indels and 21,088 SNPs between MSY and HSY. The vast majority of indels are single nucleotide or few base pairs. A large male-specific retrotransposon insertion of 8396 bp was used to develop two papaya male-specific markers, PMSM1 and PMSM2 that amplify 585 and 548 bp fragments, respectively. These two markers were tested in 11 gynodioecious and four dioecious varieties along with autosomal DNA marker 71E and male/hermaphrodite marker W11, and the results showed clear separation of male from hermaphrodite and female. PMSM1 and PMSM2 were also used to test the sex type of six sex male-to-hermaphrodite reversal mutants which are crucial materials for validating candidate genes for sex determination in papaya. Our result showed all six mutants were positive for the male-specific markers. These male-specific markers can be used to distinguish gynodioecious and dioecious cultivars in papaya seed market, and facilitate genetic and genomic research for papaya improvement.     

Transfer of the Kosena Rfk1 gene,required in hybrid seed production,from oilseed rape to turnip rape

Radiant frost is a major abiotic stress, and one of the principal limiting factors for agricultural production worldwide, including Australia. Legumes, including field pea, faba bean, lentil and chickpea, are very sensitive to chilling and freezing temperatures, particularly at the flowering, early pod formation and seed filling stages. Radiant frost events occur when plants and soil absorb the sunlight during the day time and radiate heat during the night when the sky is clear and the air is still. Dense chilled air settles into the lowest areas of the canopy, where the most serious frost damage occurs. The cold air causes nucleation of the intracellular fluid in plant tissues and the subsequent rupturing of the plasma membrane. Among the cool season grain legume crops, chickpea, lentil and faba bean and field pea are the most susceptible to radiant frost injury during the reproductive stages. The more sensitive stages are flowering and podding. Frost at the reproductive stage results in flower abortion, poor pod set and impaired pod filling, leading to a drastic reduction in yield and quality. In contrast, in the UK and European countries, frost stress is related to the vegetative stages and, in particular, the effects of frost have been studied on cotyledon, uni/tri-foliolate leaf and seedling stages during the first few weeks of growth. Few winter genotypes have been identified as frost tolerant at vegetative stages. Vegetative frost tolerance is not related to reproductive frost tolerance, and hybrids from the vegetative frost-tolerant genotypes may not necessarily be tolerant at the reproductive stage. Tolerance to radiant frost has an inverse relationship with plant age. In the field, frost tolerance decreases from the vegetative stage to reproductive stage. Unlike wheat and barley, it is difficult to analyse and score frost damage in grain legume crops due to the presence of various phenophases on one plant at the reproductive stage. The extent of frost damage depends on the specific phenophases on a particular plant. However, current studies on genetic transformation of cold tolerant gene(s), membrane modifications, anti-freeze substances and ice nucleating or inhibiting agents provide useful information to improve our current understanding on frost damage and related mechanisms. The effects of frost damage on yield and grain quality illustrate the significance of this area of research. This review discusses the problem of radiant frost damage to cool season legumes in Australia and the associated research that has been carried out to combat this problem locally and worldwide. The available literature varies between species, specific climatic conditions and origin.     

山东省冬小麦晚霜冻灾害的时空分布

为了研究山东省冬小麦晚霜冻灾害的时空分布规律,利用山东省16个农业气象观测站1981—2011年逐年冬小麦拔节期、拔节—抽穗期逐日最低气温资料,运用农业气象学和统计学的方法,对该省冬小麦拔节期的变化规律进行分析,并按照作物霜冻害等级标准同时结合山东实际,制定山东省冬小麦拔节期间霜冻害标准,按此标准对霜害数据进行统计。结果表明,山东省冬小麦常年拔节期在3月27日至4月18日,平均在4月6日,拔节期在时间分布上有提前的趋势。区域分布上,鲁西南最早进入拔节期,其次是沿胶莱河两岸从莱州湾到胶州湾地区,最迟的是半岛东部。冬小麦逐日进入拔节期的概率随日序的变化符合正态分布。霜害温度出现的累积概率随拔节盛期后日序变化呈递减趋势,递减速率可以用指数方程表达。山东省霜冻概率高的区域在从莱州湾,沿胶莱河两侧,至胶州湾、半岛西部和潍坊的东部。鲁西北西部、半岛东部由于拔节期较晚,鲁南部分地区由于受冷空气影响较小,霜冻危害的概率均较小。研究结果有利于了解霜害的分布规律,对于霜害的防御具有指导意义。     

气候变化对不同产区苹果安全越冬的可能影响

为科学评估气候变化对中国产区苹果安全越冬的影响,结合现有成果提出了分别表征果树初冬低温伤害风险、冬季持续性低温伤害风险、冬季极端低温危害风险和脱驯化期的低温伤害风险4个农业气象指标,利用1961—2015年中国苹果主产区的气象资料,分黄土高原、环渤海湾、黄河故道、西南高地和新疆5个产区,评估了气候变化对苹果安全越冬的可能影响。结果表明：苹果产区越冬期升温明显,霜冻日数和极端低温事件发生频次显著减少。初冬首次低温与初霜日间隔缩短导致渤海湾北部产区、黄河故道及北疆苹果的初冬低温伤害风险增加。越冬期持续性低温伤害风险和极端低温危害风险总体降低,特别是中高纬度表现明显,而黄土高原和新疆产区的极端低温事件发生的不确定性较大。同时黄土高原、辽宁、川西和北疆等产区苹果脱驯化期的低温伤害风险有所增加。总体上,苹果深度休眠期的冬季极端低温和持续性低温冻害风险有所降低,而初冬和脱驯化期低温冻害风险显著增加。     

The freezing characteristics of wheat at ear emergence

Wheat is occasionally exposed to freezing temperatures during ear emergence and can suffer severe frost damage. Few studies have attempted to understand the characteristics of freezing and frost damage to wheat during late development stages.

It was clearly shown that wheat appears to have an inherent frost resistance to temperatures down to −5 °C but is extensively damaged below this temperature. Acclimation, whilst increasing the frost resistance of winter wheat in a vegetative state was incapable of increasing frost resistance of plants at ear emergence. It is proposed that the ability to upregulate frost resistance is lost once vernalisation requirement is fulfilled.

Culms and ears of wheat were able to escape frost damage at temperatures below −5 °C by supercooling even to as low as −15 °C and evidence collected by infrared thermography suggested that individual culms on a plant froze as independent units during freezing with little or no cross ice-nucleation strategies to protect wheat from frost damage in the field appear to revolve around avoiding ice nucleation.     

野木瓜籽油润唇膏的研制

以野木瓜籽精炼油为主要原料,采用单因素试验和正交试验,将膏体的综合评分作为评分标准,得到野木瓜籽油润唇膏的研制配方,并对其进行卫生指标的检测。结果表明,以100 g润唇膏配方为基准,混合油添加量73.5%,混合油的组成为野木瓜籽精炼油∶霍霍巴油质量比5∶5;混合蜡添加量14.6%,混合蜡的组成为蜂蜡∶小烛树蜡质量比4∶6;凡士林添加量5.9%,肉豆蔻酸异丙酯添加量5.0%,二棕榈酰羟脯氨酸添加量1.0%,适量柠檬精油,适量茶树精油。该配方下制得的唇膏微生物指标、重金属指标均满足国家标准中的要求。     

Frost resistance mechanisms in quinoa (Chenopodium quinoa Willd.)

Quinoa (Chenopodium quinoa Willd.) is traditionally grown in the mountain regions of the Andes where frost is common. However, the physiological mechanisms responsible for the frost resistance observed in quinoa are largely unknown. For this reason, a study on cultivars of quinoa originating from the Andean highlands and from the inter-Andean valleys was performed. Frost tolerance was determined by measuring the average lethal temperature of 50% of the leaf tissues (LT₅₀) by ion leakage, and supercooling activity was assessed by thermal analysis using thermocouples. Quinoa demonstrated supercooling capacity (a mechanism that prevents immediate damage by freezing temperatures) of 5 °C. Ice nucleation temperature was always lower than the LT₅₀. This indicates that the main survival mechanism of quinoa to frost is avoidance of ice formation by moderate supercooling. The study revealed that quinoa has a high soluble sugar content, which may cause a lowering of the freezing point and therefore contributing to lower the LT₅₀. It is suggested that the content of proline and soluble sugars, such as sucrose, may serve as indicators of frost tolerance in quinoa breeding material.     

2014年一次强降温天气对杏扁的冻害过程分析及防御建议

2014年5月3—5日，张家口杏扁种植区出现了严重的霜冻害，笔者应用实时MICAPS气象资料和地面观测资料，对本次天气过程进行了天气成因、前期气候背景、预报经验指标分析，发现高低空强烈的冷平流为霜冻发生提供了基本的平流降温条件；连续的冷平流作用和强烈发展并稳定维持在张家口北侧的东北低压，是造成这次低温霜冻持续时间长的关键系统；霜冻发生前出现的降水是这次杏扁冻害造成严重损失的主要原因。准确的天气预报是杏扁冻害防御的重要基础，霜冻预报经验指标可以为杏扁的冻害防御工作提供理论参考。     

养分综合管理对马铃薯抗冻性的影响

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