板栗空苞产生的原因及防止措施分析

板栗空苞就是栗蓬中没有栗子,栗农称之为“哑巴栗”,全树都是空苞的叫“哑栗树”。在板栗生产上,这种空苞现象非常严重和普遍,一般要占15％,少数地区达到50％以上,严重影响着板栗的产量。     

向日葵秕粒增多的原因及防止措施

向日葵是一种耐盐碱、耐瘠薄,对温度、光照、水分等环境条件适应性很强的经济作物,其籽粒、花盘和茎秆具有很高的利用价值,但是由于秕粒增多,近年来种植面积有所下降。经过调查分析,我们总结出向日葵秕粒增多的原因及防止措施。     

冬暖大棚蔬菜病虫害频发的原因及综合防治措施

冬暖大棚（又叫日光温室）种植蔬菜具有建造投资较少、见效快、效益高、节约能源等优点,近几年在山东邹城发展迅速,然而随着种植面积的不断扩大,病虫害也呈现出逐年加重的趋势。积极探索病虫害频发的原因及防治措施,     

锦州地区花生减产原因及解决措施

锦州市松山新区的花生栽培具有广阔的市场需求,伴随农业种植结构调整,花生栽培面积迅速扩大,21世纪初全地区花生播种面积达2325hm^2,占总耕地面积33％。但由于近年来花生单位面积产量下降,严重影响农民生产积极性,使花生种植面积明显减少,2008年全地区花生播种面积只有900hm^2。针对本区花生栽培技术难题,进行了减产原因调查分析,并提出相应解决办法,以便为恢复花生生产提供技术指导。     

生产中玉米种子发芽率降低的原因及防止对策

发芽率是玉米种子质量优劣的重要指标之一，是种子生产单位（农户）一年生产成败与收益的重要依据。它不仅受人为因素影响而且在很大程度上受自然气候因素制约。影响发芽率的因子贯穿于从种到收，直至晾晒、加工成品入库期前的系列管理活动中。     

芹菜生产过程中一段时间叶柄变白的主要原因和解决办法

1叶柄变白的主要原因近几年来,中国各地芹菜种植面积逐年增加,栽培方式也逐年增多,芹菜品种不断更新。新品种大多是品质优,叶柄浅绿色的,然而有些地区种植的芹菜不同程度出现一段时间叶柄由浅绿色变白,过一段时间又由白变浅绿色的情况。此种现象多发生在夏秋季节和初冬季节,其主要原因有以下     

玉米倒伏的原因与防控措施

玉米是山西省种植面积最大的农作物,近几年玉米种植面积一直呈上升态势,据统计2013年山西省玉米种植面积达187万hm2,玉米产量占全省粮食产量的70%以上,因此玉米生产是山西省农业生产的重中之重。我国粮食生产实现10连增,玉米产量最高,超过稻谷成为第1大粮食作物品种。但是近年来,玉米进入花期或灌浆期以后,强对流大风降雨天气频繁出现,致使太原、晋中、忻州、长治、晋城等地玉米出现不同程度的倒伏现象,尤其是2013年,太原清徐县、晋中太谷县等地受大风降雨等因素影响,玉米倒伏更为严重,给全省玉米生产带来一定影响。为分析掌握玉米倒伏的原因,总结制定预防倒伏的措施,本文就影响玉米倒伏的相关因素做一探讨和分析。     

五十团棉花生产节本增收的主要措施

棉花是五十团的支柱产业。2008年,全团种植棉花0．7万hm^2,总产4230万奴,平均单产402kg／667m^2。随着棉花种植面积及新技术应用力度的不断增大,棉花单产、总产不断提高,但高投人、高产出的风险也在不断加大。尤其随着近年物化及劳动力成本的不断上涨,造成利润降低。因此,必须采取各种有利措施,保证棉花增产增效。     

四川茶区缺水原因及对策措施

四川位于北纬26-34°、东经97～110°,幅员辽阔,地处温带和亚热带,气候温和,雨量充沛,多酸性土,许多地方适宜茶树生长。全省各地、市、州有120多个县生产茶叶,茶叶产业发展相当快,茶园面积达173333hm2,产值21亿元,茶叶已成为四川宜茶地区农民现金收入的主要来源。省委、省政府也将茶叶产业列为四川优势特色产业之首。近年来,四川茶区缺水现象比较严重,尤其是冬旱和春旱对茶叶生产造成严重影响。     

优良早熟陆地棉新陆早32号与新陆早33号的选育及应用

棉花产业是新疆经济的支柱型产业．中绒陆地棉目前仍是我区的主要种植品种。包括早熟陆地棉、早中熟陆地棉及少数杂交棉．占棉花种植面积的70％以上。新疆棉花品质与国内外棉花品质对比．目前在纤维类型、内在品质、抗性、综合性状等方面仍有不足,培育推广早熟、高产、优质、抗（耐）病、     

种子质量纠纷的影响因素与防范措施

种子质量纠纷的成因,既有种子质量的因素,也有非种子质量的因素,而有些种子质量纠纷是由种子的虚假宣传引发的。防范种子质量纠纷的关键,是要抓好种子质量工作,建立健全的种子生产、经营档案,实事求是地进行品种广告宣传,做好因种栽培技术研究和指导,做到良种良法一齐推。     

制种玉米发芽率低的原因及预防措施

发芽率是玉米种子质量检验的4项重要指标之一，也是种子公司大量调人前非常关心的内容之一。发芽率高表示有生活力的种子多，播种后出苗数多。农四师65团近年来种植玉米制种面积较大，但是由于发芽率低，造成种子等级低，种子价格就低，给玉米制种户造成了一定的经济损失。     

酒用高粱红缨子制种技术和质量控制措施

<正>红缨子是仁怀市丰源有机高粱育种中心利用仁怀市地方小红缨子高粱品种优良单株作母本与地方特矮秆品种优良单株作父本,杂交后育成的糯性中秆中熟常规高粱品种,2008年6月通过贵州省审定(审定编号:黔审粱2008002号),2010年通过有机高粱认证,是目前国酒茅台唯一指定的有机高粱种子。1品种特征特性全生育期131d左右,叶色浓绿,颖壳红色,穗散型,子粒红褐色,千粒重20g左右。支链淀粉含量高,单宁     

辽西地区玉米杂交制种秕实的成因及预防途径

辽西是东北地区重要的玉米制种基地,每年制种面积在3.3万～4.0万hm^2。近年来由于受气候及多种相关因素的影响,各玉米制种田普遍存在秕实现象,有的还相当严重,据调查一般情况下减产8％～12％,严重的可达40％以上。辽西地区每年因秕实造成的减产可达1000万～1800万kg,直接经济损失2000万～3600万元。本文通过多年制种实践与调查分析,提出了造成秕实的主要原因及预防途径。     

Peeling has no effect on respiration and ethylene production and only minimal effect on quality of fresh white asparagus spears

Fresh white asparagus spears were subjected to peeling or left unpeeled before storage at 10 °C for 7 days. CO₂ and ethylene production rates were determined during storage, while color, toughness and DPPH radical scavenging activity as well as soluble solids, total soluble phenols and nitrate content were determined before and after storage in both peeled and unpeeled spears. Peel CO₂ and ethylene production rates were also determined during storage. Spears subjected to peeling were more tender, and had lower lightness and chroma and higher hue angle values compared to the unpeeled ones. However, both peeled and unpeeled spears had similar DPPH radical scavenging activity, soluble solids, total soluble phenols and nitrate contents. Peeling resulted in increased CO₂ and C₂H₄ production rates, but peel contributed to total increase of CO₂ and C₂H₄ production. As the measured metabolic activity of the peeled asparagus spears was similar to that of the unpeeled, peeling did not adversely affect quality during storage.     

Peeling has no effect on respiration and ethylene production and only minimal effect on quality of fresh white asparagus spears

Fresh white asparagus spears were subjected to peeling or left unpeeled before storage at 10 °C for 7 days. CO₂ and ethylene production rates were determined during storage, while color, toughness and DPPH radical scavenging activity as well as soluble solids, total soluble phenols and nitrate content were determined before and after storage in both peeled and unpeeled spears. Peel CO₂ and ethylene production rates were also determined during storage. Spears subjected to peeling were more tender, and had lower lightness and chroma and higher hue angle values compared to the unpeeled ones. However, both peeled and unpeeled spears had similar DPPH radical scavenging activity, soluble solids, total soluble phenols and nitrate contents. Peeling resulted in increased CO₂ and C₂H₄ production rates, but peel contributed to total increase of CO₂ and C₂H₄ production. As the measured metabolic activity of the peeled asparagus spears was similar to that of the unpeeled, peeling did not adversely affect quality during storage.     

Genetic analysis of flower and lateral shoot production in Gerbera

Summary An incomplete diallel cross with selfs and reciprocals was made with twelve cultivars of Gerbera jamesonii. Very significant differences occurred between GCA's of the parents for cut flower yield, earliness and number of lateral shoots. The selfs were mainly responsible for the significant SCA's.A positive genetic correlation occurs between the number of lateral shoots at anthesis of the first flower and total flower production. The phenotypic performance of parents (measured on cuttings) was poorly related to their breeding value (measured on seedlings). It is suggested that this is due to physiological differences between cuttings and seedlings.     

Spear yield and quality of white asparagus as affected by soil temperature

In three consecutive years two asparagus cultivars (Gijnlim, Grolim) were cultivated at three different temperatures in the ridge surface ranging from 12 to 26 °C to assess (1) the onset of spear yield, (2) the mean daily yield increase per plant, and (3) the establishment of spear quality defects. The objective was to determine the temperature dependence of the spear growth and quality of white asparagus with respect to different cultivars and the harvest year.

The mean time interval Δt from the beginning of the temperature treatment to harvest start was 16.5 d at the reference temperature of 20 °C. This time interval corresponded to a thermal time of 255 °C d at a base temperature of 4.4 °C. The mean yield increase per plant at the reference temperature was 17.4 g d⁻¹. The temperature dependence of Δt and was expressed by the relative change of these quantities per 1 °C alteration, which were on average 0.08 and 0.14 °C⁻¹, respectively. The frequency of quality defects (rusted spears, split spears, hollow/club-shaped spears, spears with open heads) and grade I quality depended significantly (P < 0.05) on the temperature, cultivar, and harvest year. Generally, ‘Gijnlim’ showed fewer quality defects than ‘Grolim’, whereas spears without defects were most frequent for those grown between 18 and 22 °C. With rising temperatures, the frequency of split or hollow/club-shaped spears and spears with open heads increased, while the frequency of rusted spears decreased. The derived functions of yield and quality parameters should improve the controlling of the yield and quality of white asparagus spears at varying temperatures in the ridge.     

Efficient detection of asparagus monoploids for the production of colchiploid inbreds

Summary An experiment was conducted to develop a method for monoploid seedling detection which is more efficient than making cytological examinations of twin seedlings. A recessive seedling marker gene (basal stem color) was used to detect parthenogenesis in female plants. Out of 10 seedlings showing the marker character, 9 were monoploid as expected. The frequency of parthenogenesis among single seedlings was approximately 1 seedling in 2,400. The marker gene technique increases the efficiency of cytological examination from approximately 1 or 2% to 90%.Florida Agricultural Experiment Station Journal Series No 3681     

Quantitative assessment of intact green asparagus quality by near infrared spectroscopy

NIR spectroscopy was used to assess textural parameters (maximum shear force and cutting energy) in intact green asparagus. At the same time, two commercially available spectrophotometers, which differ primarily in terms of measurement principles, were evaluated: a scanning monochromator (SM) of 400–2500 nm and a combination of diode array and scanning monochromator (DASM) of 350–2500 nm. A total of 468 green asparagus spears cv. ‘UC-157’ were used to obtain calibration models based on reference data and NIR spectral data. Both instruments provided good precision for maximum shear force, with r² values between 0.55 and 0.67 and standard error of cross-validation (SECV) ranging from 7.81 to 8.43 N, and also for cutting energy (r² = 0.60–0.74; SECV = 0.06–0.07 J). The results obtained suggest that NIR spectroscopy is a promising technology for predicting intact green asparagus quality in terms of texture. They also show that the two spectrophotometers tested provided a similar degree of accuracy for texture measurements in intact green asparagus.