Boron fertilization improves seed yield and harvest index of Camelina sativa L. by affecting source-sink

The impact of soil (1, 2 kg ha^?1) and foliar (100, 200 mg L^?1) boron (B) with control (no B) was evaluated on phenology and yield formation of Camelina each applied at stem elongation and flowering stages. Foliar (200 mg L^?1) or soil B (2 kg ha^?1) resulted in earlier flowering and maturity, increased fruit bearing branches (19.68%), number of siliqua, seeds per siliqua (4.6%), biological yield (15%), seed yield (24%), harvest index (11.4%) and oil contents (23%) than no B. Increased fruit bearing branches, seed filled siliqua or seed numbers, harvest index and oil quality can be attributed to changes in dry matter accumulated of stem with simultaneous increase in siliqua dry weight with foliar or soil applied B. In crux, foliar (200 mg L^?1) or soil applied (2 kg ha^?1) B seems promising to improve seed and oil yield, harvest index of Camelina sativa under B deficient condition.     

Organic C and N stabilization in a forest soil: Evidence from sequential density fractionation

In mineral soil, organic matter (OM) accumulates mainly on and around surfaces of silt- and clay-size particles. When fractionated according to particle density, C and N concentration (per g fraction) and C/N of these soil organo-mineral particles decrease with increasing particle density across soils of widely divergent texture, mineralogy, location, and management. The variation in particle density is explained potentially by two factors: (1) a decrease in the mass ratio of organic to mineral phase of these particles, and (2) variations in density of the mineral phase. The first explanation implies that the thickness of the organic accumulations decreases with increasing particle density. The decrease in C/N can be explained at least partially by especially stable sorption of nitrogenous N-containing compounds (amine, amide, and pyrrole) directly to mineral surfaces, a phenomenon well documented both empirically and theoretically. These peptidic compounds, along with ligand-exchanged carboxylic compounds, could then form a stable inner organic layer onto which other organics could sorb more readily than onto the unconditioned mineral surfaces (“onion” layering model).To explore mechanisms underlying this trend in C concentration and C/N with particle density, we sequentially density fractionated an Oregon andic soil at 1.65, 1.85, 2.00, 2.28, and 2.55 g cm⁻³ and analyzed the six fractions for measures of organic matter and mineral phase properties.All measures of OM composition showed either: (1) a monotonic change with density, or (2) a monotonic change across the lightest fractions, then little change over the heaviest fractions. Total C, N, and lignin phenol concentration all decreased monotonically with increasing density, and ¹⁴C mean residence time (MRT) increased with particle density from ca. 150 years to >980 years in the four organo-mineral fractions. In contrast, C/N, ¹³C and ¹⁵N concentration all showed the second pattern. All these data are consistent with a general pattern of an increase in extent of microbial processing with increasing organo-mineral particle density, and also with an “onion” layering model.X-ray diffraction before and after separation of magnetic materials showed that the sequential density fractionation (SDF) isolated pools of differing mineralogy, with layer-silicate clays dominating in two of the intermediate fractions and primary minerals in the heaviest two fractions. There was no indication that these differences in mineralogy controlled the differences in density of the organo-mineral particles in this soil. Thus, our data are consistent with the hypothesis that variation in particle density reflects variation in thickness of the organic accumulations and with an “onion” layering model for organic matter accumulation on mineral surfaces. However, the mineralogy differences among fractions made it difficult to test either the layer-thickness or “onion” layering models with this soil. Although SDF isolated pools of distinct mineralogy and organic-matter composition, more work will be needed to understand mechanisms relating the two factors.     

甜高粱茎秆含糖量遗传研究进展

甜高粱(Sorghum bicolor)是普通粒用高粱的一个变种。与粒用高粱相比,甜高粱育种研究进展相对缓慢,特别是茎秆含糖量高的亲本系创造比较滞后。开展甜高粱茎秆含糖量的遗传研究,对甜高粱亲本系选育及杂交种组配具有重要意义。本文从茎秆含糖量的评价指标入手,分别对茎秆含糖量的遗传与子粒产量及其他性状的关系、基因定位等方面的相关研究结果进行了系统地概括和归纳,并分析了当前茎秆含糖量研究的热点和亟待解决的问题。     

不同品种桑椹糖酸组分分析

分析了不同品种桑椹的糖酸组分。以33个品种桑椹的果实为试材,利用高效液相色谱技术检测,相关性分析采用相关系数法,聚类分析采用快速聚类法。结果表明,果糖和葡萄糖是桑椹的主要糖类,同一品种二者含量相当,品种之间存在差异,没有发现桑椹中含有蔗糖。所有桑椹品种含有柠檬酸、苹果酸、琥珀酸、草酸、丙酸和富马酸,绝大部分品种含有酒石酸,部分桑椹品种含有丙酮酸,柠檬酸、苹果酸和琥珀酸是桑椹中含量较高的3种有机酸,柠檬酸质量分数为41.30%～68.80%。总酸与柠檬酸、苹果酸和琥珀酸呈极显著正相关(p<0.01)。33个品种桑椹可分成五大类群,分别由10,1,5,7,10桑椹品种组成。     

降解稻草纤维素真菌的初步研究

从自然腐烂的稻草秸秆中分离筛选出126霉菌菌株,并从中筛选出10株降解稻草秸秆能力较好的菌株。其中以A242,A251降解秸秆纤维素能力较强;A321,B311降解秸秆半纤维素能力较强。A242,B311菌株的稻草粉发酵降解液中还原糖质量分数分别达到94.104 4,90.627 4 mg/g稻草粉;A321,B321菌株的稻草粉发酵降解液中木糖质量分数分别达到11.821 0,12.121 9 mg/g稻草粉。可综合其各自发酵的优势,将其作为初始菌株进行进一步的优化。     

吉林省主要果树品种果实的主要性状及糖,酸,Vc含量的测定

作者对吉林省不同产地的苹果、梨、山植、杏和葡萄的主要品种和单果重、硬度、可溶性固形物、总糖、总酸和V_c含量做了全面测定。     

马铃薯贮藏期间干物质、还原糖、淀粉含量的变化

针对生产中栽培的5个马铃薯品种贮藏期间干物质、淀粉、还原糖含量变化及其相互关系进行分析研究,结果表明,贮藏期间马铃薯不同品种块茎干物质含量有极显著差异(P<0.01);同一品种不同贮藏时期干物质含量差异不显著;不同品种、不同贮藏时期马铃薯块茎淀粉含量和还原糖含量均有极显著差异(P<0.01);贮藏期间马铃薯块茎干物质含量与淀粉含量之间有显著的正相关关系r=0.902。     

药用米酒发酵过程中的成分变化

以10种中药材和大米为原料，采用酵母菌、曲霉菌（Aspergillus kawachii,Aspergillus shirousamii)，发酵制取药用米酒。在18℃，60d的发酵过程中，测定不同试验组（对照组、添加中药粉末、添加中药浸出物组）其总酸度、总糖度、乙醇含量和参数pH值、色度的变化。结果表明：总酸度的含量不断增加，其中以中药粉末添加组的含量最高。总糖含量在发酵初期急剧下降，后期变化不大，不同试验组含量相当。采用气相色谱分析乙醇含量，中药粉末添加组中的乙醇含量高于其他2组。pH值的变化，2组呈相同的趋势，在发酵初期下降，后期又缓慢增加，色度的变化，不同试验组均前期变化较快，后期变化不大。