果园营养诊断配方施肥对琯溪蜜柚及桃产量品质的影响初探

通过土、叶样营养元素分析,土样营养元素以有效Ca含量最高,其依次顺序为：有效Ca>有效Mg>有效K>有效N>有效Fe>有效P>有效Cu>有效Zn,有效P、有效Cu、有效Zn缺乏;叶片营养元素与适量标准相比较,琯溪蜜柚叶片养分含量,有效Zn严重缺乏,有效Cu、有效P、有效Mg、有效K、有效Ca和有效Fe都处于低量范围内,有效N、有效Ca和有效Fe处于高量;桃叶片养分含量与适量标准相比较,有效Ca严重缺乏,有效N处于高量,有效K在适量范围内,其它处于低量范围内;结果表明,初步推算的琯溪蜜柚和血桃试验园的配方施肥量,均能显著提高果实产量。琯溪蜜柚试验园与对照园相比,平均亩产增加 36.15%,固酸比提高4.26%,糖酸比提高18.03%;血桃试验园与对照园相比,平均亩产增加 37.67%,总糖、总酸、Vc、固形物、可食率含量与对照相比分别提高了6.10%、6.90%、34.55%、9.28%、2.10%。     

Enhancement of revegetation on construction fill by fertilizer and topsoil application: Effect on mycorrhizal infection

The influence of topsoil and fertilizer application on denuded road construction sites was evaluated to assess its contribution to improvement of vegetation re-establishment. the study sites were within a mixed hardwood and conifer forest on crushed, unweathered subsurface material with low fertility and low biological activity. Topsoils were removed from the site, stockpiled and reapplied to the site after construction. the effect of topsoil amendment on plant growth, soil fertility, mycorrhizal infection and an index of microbial biomass were measured in field and greenhouse experiments. Plant growth on the topsoil amended field plots were greatly increased relative to treatments with fertilizer but no topsoil. Three years after establishment, dry weight production on the plots without topsoil treatment was about 40 per cent of the plots treated with topsoil. Greenhouse experiments were designed to compare fresh, dried and stockpiled topsoil. These experiments indicated that storage of the harvested topsoil for five months in a stockpile had minor effects on plant growth, soil fertility, mycorrhizal infection and microbial biomass. Topsoil volumes had to exceed 20 per cent of the total soil volume to achieve statistically significant benefits and higher ratios showed greater benefit. the percentage of mycorrhizal infection was greatest in topsoil treatments without fertilizer. the addition of fertilizer increased growth but reduced the percentage of roots forming mycorrhizae. When the total weight of infected roots was calculated, however, infection was found to be greatest with a moderate level of fertilizer (equivalent to approximately 27 kg N ha⁻¹ and 39 kg P ha⁻¹), and was less in both higher fertilizer treatments and in unfertilized treatments. Topsoil amendment increased microbial biomass nitrogen but fertilizer treatment did not.     

Comparative study on the effects of buckwheat by roasting: Antioxidant properties,nutrients, pasting,and thermal properties

The increasing need to prolong the shelf life of buckwheat has prompted the use of roasting techniques in buckwheat processing. For effective roasting, the responses of common buckwheat (CB) and tartary buckwheat (TB) to the process should be explored. Herein, the antioxidant properties, nutrients, pasting, and thermal properties of raw and roasted buckwheat flours (roasted at 200 °C for 50 s) from two CB and three TB varieties were investigated. Results showed that roasting considerably reduced the total flavonoid content (TFC) and total phenolic content (TPC) of TB. The TPC of CB was significantly improved by roasting, whereas the TFC significantly decreased. The total antioxidant capacities were consistent with the TPCs. Additionally, the colour deepened as the amount of antioxidant compounds increased. Unexpectedly, roasting enhanced the protein and fat contents of CB and decreased those of TB. Roasting improved the nutritional quality and antioxidant capacity of CB, and opposite results were obtained in TB. In conclusion, CB was more suitable to the development of roasted specialty products with nutritional applications than TB. We suggest that differences among varieties should be considered first in the buckwheat roasting process.     

盐胁迫下外源功能微生物调控水稻生长特征研究

以高产水稻品种中浙优1号为材料,设置2个盐胁迫处理(S0,正常生长条件;S1,盐逆境,3g NaCl/kg干土)和2个微生物处理(M0,对照;MM,荧光假单胞菌与巴西固氮螺菌共同接种水稻根际环境),研究了盐胁迫下外源功能微生物对水稻生长特征的影响。结果表明,与S0处理相比,S1处理下水稻植株生育期严重滞后,干物质积累量以及产量构成因子显著降低;与S1M0处理相比,S1MM处理可显著提高水稻剑叶光合速率、地上部干物质量以及产量构成因子。可见,荧光假单胞菌与巴西固氮螺菌进入稻田土壤可缓解盐逆境对水稻生长的抑制作用,提升水稻叶片光合能力、耐盐性能,并显著提高水稻分蘖能力和结实率,增加千粒重,进而增加水稻产量。     

水文分异条件下光养生物膜藻类对氮/磷的响应

光养生物膜是河流生态系统中重要的初级生产者,在河流生物地球化学循环中扮演重要角色。然而,河流水文状态及营养盐差异引起的生境异质性对光养生物膜藻类的影响未知。本研究在微型跑道池模拟流水(0.5 m/s)和静水(0 m/s)条件的基础上,通过设置不同浓度氮(1.51, 2.51和5.51 mg/L)、磷(0.1, 0.2和0.4 mg/L)及氮磷比(8, 16和32)条件培养野外采集的原位生物膜及人工基质,探究水文分异和营养变化对河流光养生物膜藻类物种组成及密度的影响。非度量多维排序(NMDS)分析结果表明,差异水文条件下,原位和建群生物膜藻类群落在梯度氮、磷和氮磷比环境中均呈现明显分离(PERMANOVA,P < 0.001),且建群生物膜中各分组藻类群落具有更明显的差异。双因素方差分析结果表明,生物膜中硅藻、蓝藻和绿藻的生长对营养盐与水文变化的响应并不一致,其中磷处理中,磷与流速单一及其交互效应显著影响了大多数藻类的生长及建群(P < 0.001);而氮处理中,氮与流速的交互效应仅对建群生物膜藻类影响显著(P < 0.001)。研究结果也发现,藻类在静水环境更有利于建群生物膜的形成,且静水-高营养盐环境更有利于蓝藻和绿藻的生长。这些结果说明,生物膜建群初期易受到水文扰动的影响,且水文分异和氮、磷影响了光养生物膜藻类的响应模式,研究为河流生态保护提供了新视角。     

蜜柚果实养分分配规律及与汁胞品质的关系

研究蜜柚果实中养分分配规律及与汁胞品质的关系,以期为改善蜜柚品质及柚园养分管理提供科学依据。随机取54个0.60-1.50 kg柚果,将果实分为黄皮层、白皮层、囊衣和汁胞等4个部位取样,分析各部位全氮（N）、全磷（P）、全钾（K）、可溶性氮（包括NH4+-N、NO3--N和氨基酸态氮（AA-N））和可溶性磷（SP）的浓度及汁胞中可溶性固形物（TSS）和可滴定酸（TA）的含量等指标。蜜柚果实中氮磷钾分配比例为（8.60±1.66）：（1.00±0.02）：（8.55±1.08）;其中,氮主要分配在黄皮层,磷主要分配在汁胞,钾在各部位分配相近。果实中可溶性N占TN的19.35% ± 2.67%,以AA-N为主;其中AA-N：NO3--N：NH4+-N分别为：15.45% ± 0.70%,2.55 ± 0.08%和1.35 ± 1.89%,并且NO3--N主要分配在白皮层,NH4+-N主要在汁胞,AA-N在各部位分配相近。果实中,SP含量约为全磷的10.63% ± 0.09%,主要分配在汁胞。相关分析发现,固酸比（TSS/TA）与SP极显著正相关,与NH4+-N显著负相关。果实中N、P、K及其可溶性形态在各部位分配的规律不同,建议遵循“高氮、低磷、高钾”的原则进行科学施肥。养分分配显著影响果实品质,其中SP浓度可能是影响汁胞固酸比的主要因素。     

不同木豆品种的生物学和品质特性比较研究

以广西地方木豆品种为对照,与引进的其他7个木豆新品种进行田间比较试验,评价引进木豆品种的种性和生态适应性.结果表明:不同木豆品种的根、茎、叶、花、荚、籽粒、株型等形态特征,萌芽、生长、开花、生长期、抗病虫性等生长特性以及茎、叶、籽粒的粗蛋白、粗脂肪、粗淀粉含量都有显著差异.根据不同品种的表现:广西品种、非洲品种、缅甸品种、ICPL87119比较适应喀斯特石山区荒地、山地种植,可作为饲料、水土保持、生态保护、薪炭林等用途,ICPH8、IC-PL87091可作蔬菜和粮食用,其中ICPL87091是一个比较有希望的品种.     

萝卜肉质根产量与主要性状相关及通径分析

试验运用相关及通径分析,对萝卜杂交组合的株高、展开度、外露长、叶重、叶片长、叶片宽、叶片数、根长、根粗9个相关农艺性状与肉质根产量进行了分析。结果表明,萝卜杂交组合单根重与其相关性状的直接通径系数是：株高-0.3176、展开度0.3338、外露长0.7369、叶重-0.1175、叶片数0.0626、叶片宽-0.1773、叶片长0.0267、根长0.4839、根粗0.4420。外露长〉根长〉叶重〉株高〉展开度〉根粗〉叶片长〉叶柄长〉叶片数〉叶片宽〉叶柄宽。     

胡萝卜微粉物理特性和营养成分的影响因

胡萝卜微粉制备中,影响微粉物理特性及营养成分的试验分析表明:热风和微波干燥获得的胡萝卜微粉容积密度大,冷冻干燥的胡萝卜微粉容积密度小.微波干燥获得的胡萝卜微粉溶水性好,其次是冷冻干燥;胡萝卜生粉比熟粉溶水性好.胡萝卜生粉的氨基酸质量比高于熟粉和冻融粉;真空冷冻干燥生胡萝卜,粉碎粒径小于240目时,氨基酸质量比高.经过冻融处理的胡萝卜微粉V_c质量比高于其生粉和熟粉;冷冻干燥的胡萝卜微粉V_c质量比高.类胡萝卜素质量比随着粒径减小而减小;冷冻干燥冻融处理的胡萝卜,在粉碎粒径为80～120目时,类胡萝卜素和V_c质量比高.     

Einfluss von grundwasser und trittbelastung auf den prozess der torfmineralisation und die stoffbilanzen: Influence of ground water and footprints on process of peat mineralization and nutrient balances

Pasture with burdening on peat-bog done four times a year has more positive effects on the water balance than twice grassland use. The saving of water that has been determined by lysimeters evokes no positive effects on the N-, P-, K- or Ca-balance. Due to the lower depth of the plant roots under lowland bog used for pasture more nutrients were leached into the ground water. The soil compression leads to anaerobic conditions. Therefore the phosphorus becomes more mobile and migrates into the outlet. The effect on the peat mineralization and the nutrient balances was not as clear as assumes, because other parameters like the combination of the vegetation formation and the age of the plants also had a strong influence on the factor. The younger plants from the pastures have show higher nutrient contents so that the nutrient export is higher and the balance becomes more negative.