不同海拔地区对大麦农艺性状和品质的影响

采用二因素随机区组设计方法,在4个不同海拔地区进行7个品种大麦试验,研究海拔高度对大麦农艺性状、产量及品质的影响。结果表明:随着海拔高度升高,大麦生育期延长,株高增高;在试验海拔范围内大麦产量随海拔升高呈先升高后降低的趋势;不同海拔地区间大麦穗数和穗粒数差异不显著;生育期和株高对海拔差异反应敏感,千粒质量对海拔差异不敏感;各性状指标在品种间表现出相对稳定性。在品质性状方面,大麦籽粒的发芽率、筛选率、蛋白质含量、麦芽浸出物、库尔巴哈值均呈随海拔升高而逐渐降低的变化趋势,并且不同海拔间差异显著(P0.05)。籽粒淀粉含量和可溶性氮含量随海拔升高先升高后降低,品种间差异不显著,不同海拔间差异显著(P0.05)。     

环境因素对青藏高原栽培大麦穗粒数空间分布的影响

为了探究环境因素对青藏高原栽培大麦穗粒数的影响,利用121个样点的地理、气候、土壤因子数据,研究了青藏高原栽培大麦穗粒数的分布特征。结果表明:在地理水平方向上,青藏高原栽培大麦穗粒数呈现斑状交错分布的格局,栽培大麦穗粒数的高值主要集中在西藏林芝地区和山南地区,穗粒数的低值主要集中在四川地区;在地理垂直方向上,青藏高原栽培大麦集中分布在海拔3500~4000 m,以海拔2500 m以下的栽培大麦穗粒数最多,随着海拔的升高,栽培大麦穗粒数逐渐增加,在海拔3500~4000 m达到最大值,此后,随着海拔的升高,栽培大麦穗粒数逐渐降低,海拔4500 m以上的穗粒数最少。环境因素对栽培大麦穗粒数的影响表现为土壤速效磷含量>年均降水量>日平均气温≥0℃积温>地理纬度>土壤pH含量>土壤全钾含量>土壤速效氮含量>海拔高度。     

优质小麦重要性状的相关分析

利用7个优质小麦品种（品系），分析了优质小麦籽粒产量与品质性状的关系，以及品质性状之间的关系。结果表明，籽粒产量与蛋白质含量、湿面筋含量和干面筋含量等营养品质性状呈极显著或显著负相关，与Zeleny沉淀值、面团形成时间和稳定时间等加工品质性状相关不显著。蛋白质含量与湿面筋含量和干面筋含量逗号地极显著正相关，湿面筋含量与干面筋含量呈极显著正相关。Zeleny沉淀值与面团形成时间和稳定时间呈显著或极显著正相关，面团形成时间与稳定时间呈极显著正相关。据此提出优质高产结合改良的重点是协调好粒产量与加工质量，充分利用蛋白质优质基组合。     

氮肥施用量及施用时期对小麦品质性状的影响

为了探明不同氮肥运筹对西南麦区小麦品质性状的影响,以小麦品种(系)R210和川农25为材料,采用2因素3水平随机区组设计研究了施氮量及施氮时期对小麦品质性状的影响.结果表明,蛋白质及其组分含量、干面筋含量、沉淀值和稳定时间、粉质质量指数均随施氮量的增加而提高.施氮时期对品质性状的影响表现为:全施底肥有利于提高沉淀值、粉质质量指数及醇溶蛋白含量;采用底肥∶三叶期肥=1∶1的方式有利于提高GMP含量;采用底肥∶三叶期肥∶孕穗期肥=5∶2∶3的方式,有利于提高干面筋的含量,降低弱化度.不同品种的优质栽培方式不同,R210以底肥∶三叶期肥∶孕穗期肥=5∶2∶3,施用纯氮18 g/m2品质最优,川农25以全施底肥,施用纯氮18 g/m2品质最优.     

小麦新品种川农16品质性状的杂种优势分析

为了解品质性状杂种优势的遗传特点,以小麦新品种川农16为亲本组配56个杂交组合,测定其F1的蛋白质含量、吸水率、形成时间、稳定时间、公差指数、湿面筋含量、沉淀值和评价值等8个品质性状的超亲和对照杂种优势。结果表明,品质性状杂种优势普遍存在,除吸水率和公差指数外,绝大多数组合在其余6个品质性状上均表现为正向超亲和对照优势,说明利用杂种优势改良小麦品质性状,尤其是形成时间、稳定时间、评价值及沉淀值等品质性状是完全可行的。     

海拔对啤酒大麦产量和品质的影响

为丰富大麦立体栽培理论,更好地推动高海拔地区大麦的生产,通过不同海拔种植大麦试验,分析了海拔对大麦农艺性状、品质及产量的影响。结果显示,随海拔升高大麦生育期显著延长,株高显著增高,千粒重增大,籽粒发芽率和蛋白质含量显著降低,麦芽浸出物和库尔巴哈值先升高后降低,可溶性氮先降低再升高;海拔对产量也有明显影响,在试验区内产量随海拔升高呈现先升高后降低的趋势。海拔对两个大麦品种的产量和品质的效应相同。因此,生产上应因地制宜,发挥区域优势,重视海拔对大麦品质的调控作用,以改善大麦的品质。     

优质小麦品质性状的环境变异研究

为了明确不同环境对优质小麦品种品质性状的影响,为小麦优质育种、优质栽培和品质区划提供依据,利用河北省优质小麦区试的６个优质品系,种植于藁城、石家庄、衡水和邢台,分析生长于不同地点的不同小麦品系的品质性状变异,不同试点对品质性状的作用和不同品质性状的稳定性。结果表明,不同品系的品质性状表现出不同的变异性。不同试点对小麦主要加工品质性状（沉降值、面团形成时间和稳定时间）的正向作用呈现规律性,表现为邢台     

BNS型杂交小麦不同出粉点面粉的品质特性

为给BNS型杂交小麦的进一步推广应用提供参考依据,以BNS低温敏感雄性不育系衍生的两个杂交小麦及常规小麦品种百农矮抗58为材料,研究了制粉系统各出粉点面粉的品质特性.结果表明,不同出粉点的面粉品质性状间存在差异,皮磨粉的灰分含量少,白度值、干湿面筋含量、稳定时间、峰值黏度、最终黏度、回生值等均最高;心磨粉的粗蛋白含量、灰分含量、破损淀粉含量、吸水率、形成时间、弱化度等随出粉点后移呈升高趋势,而白度、干湿面筋含量、稳定时间、峰值黏度、低谷黏度、稀懈值、最终黏度、回生值等随出粉点后移而降低;同一出粉点不同材料的品质特性具有明显差异.杂交小麦不同出粉点品质的变化趋势与常规小麦基本一致.     

不同海拔高度对稻米品质性状的影响

对10个杂交稻组合在同一生态区5个不同海拔高度12个品质性状的变异特点进行了研究.结果表明,不同品质性状在不同海拔高度的变异存在很大差异,糙米率、精米率、粒长相对稳定,各组合平均变异系数仅为0.75%,0.60%和3.16%;而垩白度、垩白粒率波动较大,各组合平均变异系数高达92.28%和66.54%.通过聚类分析,可根据稻米品质性状在不同海拔高度的变异系数大小划分为3种类型,第1种是对气候条件变化最敏感的生态敏感型,如垩白度、垩白粒率,第2种是对气候条件变化反应迟钝的生态迟钝型,如糙米率、精米率、粒长,第3种是介于二者之间的中间型.随海拔升高,灌浆结实时间延长,整精米率增大,垩白度、垩白粒率变小,说明高海拔有利于改善稻米品质.     

不同年代冬小麦品种籽粒产量与品质的演变及其对氮肥的响应

为给小麦高产优质品种的选育及调优栽培提供理论依据,以20世纪50至90年代育成的32个代表性冬小麦品种为材料,研究了小麦籽粒产量与品质的演变规律及其对氮肥响应的变化。结果表明,小麦穗粒数、千粒重和产量均随品种育成年代的推进呈增加趋势;施氮增加了不同年代小麦穗数、穗粒数和产量,但降低了千粒重。其中,20世纪90年代的小麦品种穗粒数对氮肥响应最敏感,千粒重最不敏感,因此该时期小麦的产量在施氮条件下增产显著。籽粒蛋白质含量和湿面筋含量均随年代的推进呈降低趋势,但蛋白质积累量呈增加趋势。淀粉含量和沉降值随年代先降后升,而降落值先升后降。除直链淀粉和支链淀粉含量外,氮肥对其他品质指标的影响均达到显著水平。不同年代小麦品种的各品质指标对氮素响应不同,早期品种的籽粒蛋白质含量和淀粉含量对氮肥响应较现代品种敏感。氮肥对20世纪70年代品种的湿面筋含量、80年代品种的沉降值和90年代品种的降落值影响显著。相关性分析表明,产量与蛋白质含量、湿面筋含量、沉降值呈负相关,与淀粉含量呈正相关;蛋白质含量与湿面筋含量、沉降值呈正相关。说明品种改良提高了冬小麦产量,但对小麦不同品质性状有不同的影响,增施氮肥可提高小麦产量和蛋白质含量。在保证小麦高产的前提下,稳定小麦品质是今后品种改良与合理施肥的重要目标。     

Variability in dehydrodiferulic acid composition of durum wheat (Triticum durum Desf.) and distribution in milling fractions

The dehydrodiferulic acid content of different common and durum wheat grains and milling fractions was determined by an HPLC procedure. The 8-O-4′, 5–8′ benzofuran, 5–8′ and 5-5′ dehydrodimers were identified in all samples studied and occurred in decreasing relative amounts, respectively. Durum wheats were twice as concentrated in dimers as common wheats. An important genetic variation for dehydrodiferulic acid content was shown within durum wheat grains, whereas the agronomic conditions had no effect. There was 10 to 20 times more dehydrodiferulic acids in external layers (aleurone, bran) than in the starchy endosperm of durum wheat grains. The content and composition in dimers of the inner endosperm did not vary according to genotypes and cultivation conditions. The ratio of dehydrodimers to monomers of ferulic acid which represented an index of dimerisation, was 1·6 times higher in the external layers of the grain than in the endosperm. No relation was found, however, between the degree of ferulic acid dimerisation and the milling behaviour of durum wheat grains.     

Bread-making performances of durum wheat semolina,as affected by ageing

The present study addresses the influence of ageing on the bread-making performances of durum wheat semolina by bread image analysis. Bread loaves were produced from semolina samples stored in 4 different packaging materials for up to 150 days. Sampling and bread-making trials were performed every 15 days. Results showed that ageing does affect durum wheat semolina bread-making performances, highlighting that storage time, rather than the type of packaging material, is the main factor determining quality changes in the final bread samples. In particular, a change in the crust colour parameters and a reduction of the bread slice area and height by 20–35% were observed with increasing semolina storage time, along with a slight increase of crust % area. The change in farinographic parameters of dough suggests that the observed reduction of technological quality might be due to increased stiffness and reduced extensibility of gluten occurring in aged semolina. Unlike common wheat flours, which usually improve their technological features during ageing, durum wheat semolina is negatively affected in its quality by storage. The study highlights the importance of considering bread-making performances among the quality parameters to be taken into account for the shelf life evaluation of durum wheat semolina.     

Investigation of amber durum wheat for production of yellow alkaline noodles

Samples of Canadian amber durum wheat varieties, of various protein content and a composite of export cargo samples, were milled to yield straight-grade and patent flours by reducing semolina and processed into yellow alkaline noodles (YAN). Samples of Canada Hard White Spring (CWHWS) and Canada Western Red Spring (CWRS) were included for comparative purposes. YAN from durum wheat displayed a colour advantage over CWRS and CWHWS YAN. The durum YAN displayed an approximate 9–20 unit greater b* (yellowness) value than CWRS and CWHWS at 2 and 24 h after preparation. This relates to greater yellow pigment and flavonoid contents in the durum flours. All durum wheat YAN exhibited excellent noodle brightness, which was retained over time due to lower levels of the enzymes polyphenol oxidase (PPO) and peroxidase (POD). Durum noodles displayed significantly fewer specks than CWRS and were comparable to CWHWS. Durum wheat YAN cooking quality was equal to or slightly superior to CWRS and CWHWS. Durum wheat flour refinement imparted no significant effects on cooked noodle texture (maximum cutting stress, recovery, resistance to compression). However, the various texture parameters improved with durum wheat protein content and gluten strength.     

Influence of the addition of buckwheat flour and durum wheat bran on spaghetti quality

The quality of nine spaghetti typologies, produced by using wheat durum semolina as a base plus the addition of buckwheat and durum wheat bran, was investigated. The quality of the produced spaghetti was compared with that of spaghetti made only of durum semolina (CTRL). Tests were run on the samples to determine breakage susceptibility and colour of dry spaghetti, the cooking resistance, instrumental stickiness at optimal cooking time (OCT) and overcooking, the cooking loss and sensorial attributes at the optimal cooking time. Results suggest that the breakage susceptibility decreases with the addition of 15% and 20% bran, the spaghetti dry colour changes with the addition of buckwheat flour and bran compared to the spaghetti made only of durum semolina, while the cooking resistance, instrumental stickiness and the cooking loss, in general, were equal to that of the CTRL. However, the addition of buckwheat flour and bran affected the sensorial attributes differently.     

Baking quality of emmer-derived durum wheat breeding lines

Durum wheat (Triticum turgidum L. var. durum) is used predominantly for pasta products, but there is increasing interest in using durum for bread-making. The goal of this study was to assess the bread-making potential of 97Emmer19, an Emmer wheat (Triticum turgidum L. var. dicoccum) and in breeding lines derived from crosses of 97Emmer19 with adapted durum wheat cultivars. 97Emmer19 and its progeny were evaluated in 2005 and 2006 along with five durum wheat cultivars. Three bread wheat (Triticum aestivum L.) cultivars were included as checks to provide a baseline of bread making quality observed in high quality bread wheat cultivars. 97Emmer19 exhibited higher LV than all the durum wheat checks and approached the LV achieved with the bread wheat cultivar ‘AC Superb’. Breeding lines derived from 97Emmer19 had higher LV than those of the durum wheat checks, confirming that this trait was heritable. In general, durum wheat cultivars with elevated gluten strength and/or increased dough extensibility were noted to have higher LV. Dough extensibility appeared to be a more critical factor as gluten strength increased. These results indicate that there is potential to select for genotypes with improved baking quality in durum breeding programs.     

Investigation of amber durum wheat for production of yellow alkaline noodles

Samples of Canadian amber durum wheat varieties, of various protein content and a composite of export cargo samples, were milled to yield straight-grade and patent flours by reducing semolina and processed into yellow alkaline noodles (YAN). Samples of Canada Hard White Spring (CWHWS) and Canada Western Red Spring (CWRS) were included for comparative purposes. YAN from durum wheat displayed a colour advantage over CWRS and CWHWS YAN. The durum YAN displayed an approximate 9–20 unit greater b* (yellowness) value than CWRS and CWHWS at 2 and 24 h after preparation. This relates to greater yellow pigment and flavonoid contents in the durum flours. All durum wheat YAN exhibited excellent noodle brightness, which was retained over time due to lower levels of the enzymes polyphenol oxidase (PPO) and peroxidase (POD). Durum noodles displayed significantly fewer specks than CWRS and were comparable to CWHWS. Durum wheat YAN cooking quality was equal to or slightly superior to CWRS and CWHWS. Durum wheat flour refinement imparted no significant effects on cooked noodle texture (maximum cutting stress, recovery, resistance to compression). However, the various texture parameters improved with durum wheat protein content and gluten strength.     

A micro-method for the determination of Yellow Pigment Content in durum wheat

Colour is an important component of durum wheat quality affecting consumer’s choice. Pasta colour is the result of the carotenoid pigments accumulated in the seed endosperm and of the enzymatic activities responsible for their degradation. Thus, increasing yellow colour is a valuable goal for improving the commercial and nutritional values of durum wheat products. This work reports the set up of a micro-method for the determination of Yellow Pigment Content (YPC) in durum wheat. The novel method, although similar in principle to the Official Method AACC 14-50, allows the use of micro-amount of samples (10–100 mg), a condition that for durum wheat corresponds to a single kernel, and micro-amount of extraction solvent (water-saturated 1-butanol, 250–500 μL). These improvements together with a short extraction time lead to significant benefits from the practical and the economic point of view. The improved method has been validated using nine durum wheat cultivars extracted in 15 min with the ultrasonic bath. The YPC was calculated by reading the absorbance at 435 nm after the manual injection of an aliquot of extract directly into a UV–Vis HPLC detector. The results obtained were comparable and not significantly different from the Official AACC Method 14-50.     

Path analysis of genotype × environment interactions in rainfed durum wheat

This study was investigated to analyze genotype × environment (GE) interactions for grain yield and its components and to investigate the mechanism by which the stability of grain yield is achieved in rainfed durum wheat. Twenty-four durum wheat genotypes (breeding lines, old, and new varieties) along with one old bread wheat cultivar were tested in 21 diversified rainfed environments during 2010–2013 cropping seasons. The data were analyzed by path analysis model which is composed of a main effect and four multiplicative effects. The flowering time (X1), maturity time (X2), plant height (X3), and 1000-kernel weight (X4) were assumed to be sequential characters for the development of grain yield productivity (Y) in rainfed durum wheat. A high relationship (p < .01) between observed and expected yields of genotypes in different environments confirmed the validity of the causal scheme adopted in the analysis. Comparison the estimates of components provided information on the degree of response of each genotype to the environmental stresses. The results indicated that higher grain yields are associated with higher kernel weight (v₄), which resulted from early flowering (v₁), and so more emphasis should be given to these traits for the improvement of yield potential in durum wheat under highland rainfed conditions of Iran. Positive correlation of stability variance (σ²) with v₄ component indicated that the kernel weight is the main contributor towards GE interaction for grain yield in rainfed durum wheat.     

Durum wheat breadmaking quality: Effects of gluten strength,protein composition,semolina particle size and fermentation time

The effects of particle size of granulars (semolina and flour combined), gluten strength, protein composition and fermentation time on the breadmaking performance were compared for eleven durum wheat genotypes of diverse strength from North America and Italy grown in the same environment. All genotypes were γ-gliadin 45 types (low-molecular weight glutenin subunit 2 patterns) associated with superior pasta-making quality. Three cultivars with high-molecular weight glutenin subunit 20 exhibited relatively weak gluten, confirming that this subunit is associated with weakness in durum wheat. Gluten strength as measured by a range of technological tests was directly and strongly related to the proportion of insoluble glutenin (IG) in granulars protein as determined by a spectrophotometric procedure. Reducing the particle size of granulars by gradual reduction shortened development time in both the farinograph and mixograph. Reducing granulars also increased starch damage and, accordingly, farinograph water absorption, but remix-to-peak baking absorption was unaffected due to increased fermentation loss for finer granulars. Neither loaf volume, nor remix-to-peak mixing time were affected by the particle size of the granulars indicating that regrinding is not an asset for baking provided there is adequate gassing power. Loaf volume was directly related to gluten strength and IG content, and inversely related to residue protein, a non-gluten containing fraction. When fermentation time was reduced from the standard 165 to 90 min and 15 min, all genotypes exhibited a progressive increase in loaf volume. Therefore, regardless of strength, short fermentation time is preferred when high volume durum wheat bread is desired. Some of the stronger durum genotypes exhibited remix-to-peak bread volume comparable to that expected of good quality bread wheat, indicating that there is potential to select for genotypes with improved baking quality in conventional breeding programs by screening for high content of insoluble glutenin.     

Wheat stem sawfly (Cephus pygmaeus L.) damage; impacts on grain yield, quality and marketing prices in Anatolia

This study aimed to draw the attention of the all stake holders attention to an underestimated insect pest of wheat in Southeastern Anatolia. The field studies were carried out in the experimental field of GAP Training, Extension and Research Center in Koruklu in 2003–2004 cropping season.

It was found that the number of sawfly damaged spikes varied between 6 and 12% in durum wheat and 8 and 12% in bread wheat. Comparing healthy grains, grain weight spike⁻¹ decreased significantly, giving 0.430 g less kernel weight in durum wheat and 0.385 g in bread wheat. Some of the grain quality characteristics of both sawfly damaged and healthy spikes were tested and it was found that protein content (%) in durum wheat, and 1000 kernel weight in bread wheat were reduced significantly, whilst, the SDS sedimentation value in bread wheat increased significantly for sawfly damaged grains. Grain yield losses by sawfly infestation were found to be 2.23% in durum wheat and 3.32% in bread wheat. Marketing price studies showed that sawfly damage reduced it significantly, resulting in $ 0.016 kg⁻¹ less price in bread wheat. But this was not serious for durum wheat.

It was concluded that income loss, depending on grain yield loss, un-harvestable broken spikes and lower marketing price of sawfly damaged grains, could be no less than $ 68.8 ha⁻¹ in durum wheat and $ 68.6 ha⁻¹ for bread wheat. Therefore, some control methods are required for sawfly infestation, where damage is already over the economic threshold (10–15% stem cut by pest) especially in bread wheat.