温室小型西瓜光合生产与干物质积累模拟模型

在借鉴国内外温室蔬菜作物光合生产和干物质积累模拟模型的基础上,根据温室小型西瓜的试验数据,确 定有关模型参数,建立了温室小型西瓜光合生产和干物质积累模拟模型,模型包括叶面积指数动态模型、光合生产 动态模型和干物质积累动态模型。模型利用有效积温对叶面积指数LOGISTIC方程建立叶面积指数动态模型,同时 光合作用模型还引用简便有效的高斯积分法计算冠层每日的总同化量,既考虑了光合有效辐射的日变化规律,又考 虑了太阳高度角的变化对冠层反射率的影响;此外,模型还考虑了温度对呼吸作用的影响,确定了温室小型西瓜的 碳水化合物转化成干物质的系数CF。通过不同品种、不同播期下的干物质积累动态的模型检验,表明模型有较强的 精确性、机理性和实用性。     

果树光合作用数学模拟的研究进展

以数学模拟为主线,系统综述了果树单叶光合模型、冠层结构模型、冠层辐射分布模型和冠层光合模型的研究进展;并对果树冠层光合作用有较大影响的因子如叶面积指数、太阳高度角、叶倾角分布、群集因子、消光系数、直接辐射和散射辐射等对冠层光合速率影响的数量关系进行了系统分析。研究表明对果树冠层光合影响最大的因子是太阳高度角和果树的冠层结构。能够模拟三维冠层光合作用,并且能够响应多种环境条件的动态模型是当今果树光合建模的发展方向。     

水分对作物生长发育影响的模拟研究进展

作物生长模拟模型是进行作物生产精准管理和智能决策的有力工具.现介绍了水分对作物生长发育影响的模拟研究的发展现状和应用效果,分别从水分对作物叶面积指数、光合作用、干物质生产与分配、作物产品质量影响的模拟进行了总结;提出了水分对作物生长和发育影响的模拟研究存在的问题.     

根区温度对甜瓜幼苗生长的影响

通过对日光温室甜瓜幼苗根区不同温度处理,研究了根区温度对甜瓜幼苗生长的影响.结果表明:根区低温使甜瓜幼苗叶片数、株高、叶面积、干物质积累、根系活力、植株含水量、水分利用效率降低,而根冠比增加.     

甜瓜、棉花套种植株群体生长动态研究

针对新疆吐鲁番地区普遍采用的瓜棉复合种植模式与单作甜瓜、棉花的个体和群体生长动态进行了比较研究。结果表明:采取合理的栽培管理方式,瓜棉复合种植并不影响甜瓜的正常生长发育,可以获得与单作甜瓜相近的产量。复合种植棉花与单作棉花比较,共生期内棉花植株的生长优于单作棉花;由于前期奠定了良好的生长基础,甜瓜收获后复合种植棉花个体、群体生长状态远优于单作棉花。瓜棉复合种植可建立良好的作物群体结构,在各生长发育期,复合种植模式的田间叶面积指数、光合势和群体生长率均优于单作甜瓜和单作棉花,可有效提高光能利用率。     

NaCl胁迫对甜瓜幼苗生长的影响

在盆栽条件下研究了NaCl胁迫对厚皮甜瓜黄河蜜和薄皮甜瓜白沙蜜幼苗生长的影响。结果表明:NaCl 胁迫下,甜瓜幼苗的高度、株叶面积、地上部鲜重和干物质积累均受到抑制,且这种抑制作用具有浓度和时间依赖性;在0-100mmol／L浓度以内,甜瓜幼苗对NaCl胁迫有缓冲、调节、适应的能力;NaCl对白沙蜜幼苗生长的相对抑制作用要强于对黄河蜜幼苗。厚皮甜瓜可作为西北地区微咸水灌溉和轻盐碱地生产的经济作物之一。     

不同体积椰糠与珍珠岩混合基质对甜瓜幼苗生长的影响

以薄皮甜瓜品种"日本甜宝"为试材,研究了不同体积的椰糠与珍珠岩混合基质对营养钵中甜瓜幼苗生长和幼苗质量的影响,以期为甜瓜无土育苗提供参考依据。结果表明:不同的育苗基质体积对甜瓜幼苗的株高、叶片数、叶面积、地上下部干鲜质量、根冠比、壮苗指数、光合速率、蒸腾速率和根系琥珀酸脱氢酶活性均有明显的影响。育苗体积不仅影响了幼苗的生长指标、同化物积累、光合特征和根系吸收功能,同时影响了同化物的分配特性和幼苗质量。育苗基质体积较小时,基质水肥供应及其缓冲性的不足制约了幼苗的生长发育,而当育苗基质体积超过290mL时,根际较大的保湿性也不利于具有耐旱性的甜瓜幼苗的生长发育。试验初步证明,290mL是甜瓜基质育苗的适宜体积。     

作物秸秆还田配施复合生物茵剂对棚室连作甜瓜植株生长发育的影响

以"潍科厚甜1号"网纹厚皮甜瓜为试材,研究了不同作物秸秆还田配施布氏乳杆菌、放线菌等为主要成分的复合生物菌剂对日光温室连作甜瓜生长发育的影响,以期为设施甜瓜高效栽培提供依据。结果表明:甜玉米和小麦秸秆还田配施复合生物菌剂均可显著促进连作甜瓜的根叶碳、氮代谢水平,表现为功能叶片光合速率和PSⅡ最大,光化学效率和实际光化学效率显著提升;碳、氮代谢产物蔗糖、可溶性糖、脯氨酸、游离氨基酸和可溶性蛋白质含量呈不同程度增加;根系硝酸还原酶活性、谷氨酰胺合成酶活性和根系活力显著提升。甜玉米和小麦秸秆还田配施复合生物菌剂促进了连作甜瓜株高、茎粗、单株叶面积以及根、叶干物质积累,甜瓜生育进程加快,促生作用效果以甜玉米秸秆还田配施复合生物菌剂处理最佳。因此,温室连作甜瓜进行甜玉米秸秆还田15 000kg·hm~(-2)+定植前复合生物菌剂蘸根和定植后15d进行复合生物菌剂20mL·株~(-1)灌根处理可为田间生产参考。     

施用钛肥后植物的特点

<正>水稻:促进水稻生育进程,叶面积指数大,叶片活力强,提高光合生产率,增加干物质的积累,促进分蘖产生,增加     

西瓜高产的生理基础

对西瓜不同品种、不同密度的干物质和叶面积增长动态及其与光合因素的关系进行了研究.结果表明,干物质及叶面积迅速增长期(直线增长期)约在开花前后10d左右,是栽培管理上应特别注意的时期.最适栽植密度为1000—1100株·666.7m~(-2),在此密度下,到达临界叶面积指数(0.9829)时间最短,且最大叶面积指数值最高.每666.7m~2产量4000kg以上的田块,每666.7m~2光合势应达20000m~2·d~(-1)以上,且膨瓜期的光合势占总光合势的2/3以上.     

Dry-matter production in a tomato crop: comparison of two simulation models

TOMSIM(l.O) and TOMGRO(l.O) are two dynamic models for tomato growth and development. Their submodels for dry matter production are compared and discussed. In TOMSIM(l.O), dry matter production is simulated by a modified version of SUCROS87 (Spitters et al., 1989). Single leaf photosynthesis rates are calculated separately for shaded and sunlit leaf area at different depths in the canopy, according to the direct and diffuse components of light; daily crop gross assimilation rate (A) is computed by integration of these rates over the different depths and over the day. In TOMSIM(l.O) leaf photochemical efficiency (e) and potential leaf gross photosynthesis rate at saturating light level (Pgmax) both depend on temperature and C02 level. In TOMGRO(l.O) crop gross photosynthesis rate is calculated by the equation of Acock et al. (1978); e is a constant and Pg max is a linear function of C02. In both models leaf photosynthesis characteristics are assumed to be identical in the whole canopy. Maintenance respiration (Rm) and conversion efficiency (Cf) are taken into account in the same way, except that root maintenance respiration is neglected in TOMGRO(l.O). For both models a sensitivity analysis was performed on the input variables (light intensity, temperature, C02 and leaf area index (LAI)) and on some of the model parameters. Under most conditions considered, simulated A was found to be 5-30% higher in TOMSIM(l.O) than in TOMGRO(l.O). At temperatures above 18°C Rm was also higher in TOMSIM(l.O), and C, was 4% higher in TOMGRO(l.O). The two models were very sensitive to changes in e and to a lesser extent to changes in the light extinction coefficient, whereas the scattering coefficient of leaves had hardly any effect on the simulated A. TOMGRO(l.O) appeared to be rather sensitive to the C02 use efficiency, whereas at ambient C02 level mesophyll resistance was quite important in TOMSIM(l.O). Four sets of experimental data (differences in cultivar, C02 enrichment and planting date) from Wageningen (The Netherlands) and Montfavet (southern France) were used to validate the models. Average 24 h temperature and average daily C02 concentration values were used as input to the models. For the Wageningen experiments, hourly PAR values were calculated from the daily global radiation sum by TOMSIM(l.O) and used as input in both models. For the Montfavet experiment, average hourly PAR measurements were used. Also measured LAI, dry matter distribution and organ dry weights (for calculation of Rm) were input to the simulation. In the Wageningen experiments, total dry matter production was simulated reasonably well by both models, whereas in the Montfavet experiment an under-estimation of about 35% occurred. TOMGRO(l.O) and TOMSIM(l.O) simulated almost identical curves in all four experiments. Strong and weak points of both models are discussed.     

Modelling the effects of soil water potential on growth and quality of cut chrysanthemum (Chrysanthemum morifolium)

A complete dynamic model was developed to describe the effects of soil water potential (WP) on the growth and external quality of standard cut chrysanthemum (Chrysanthemum morifolium) in order to optimise water management of greenhouse crops. Experiments using chrysanthemum cv. ‘Jinba’ with different planting dates and levels of water treatment were conducted in a lean-to type greenhouse from 2006 to 2008. The dynamics of leaf area index (LAI), dry matter partitioning, and external quality traits (plant height, number of leaves per plant, flower-head diameter and peduncle length) were first determined as functions of accumulated photothermal index (PTI). Impacts of WP on leaf photosynthetic rate, LAI, dry matter partitioning, and the external quality traits were quantified via introducing the experimentally identified effects of WP on the parameters in the light response curve of leaf photosynthetic rate and the PTI-based functions. These quantitative relationships were incorporated into a generic crop growth model SUCROS. Using independent experimental data, the model was found to give good predictions for biomass production, dry weight of organs, and the external quality traits of the chrysanthemum cultivar grown under different levels of water supply. The coefficient of determination (r²) between the predicted and measured results was 0.91 for LAI, 0.88 for biomass production, and varied between 0.83 and 0.93 for organ dry weight and the external quality traits. Further evaluation is needed when applying this model to a wider range.     

ALCEPAS,an onion growth model based on SUCROS87. II. Validation of the model

Summary

A dynamic simulation model for onion growth at potential production level (ALCEPAS), presented in a previous paper, was validated using data on leaf area index, bulb and green leaf dry-matter production, bulb formation and day of fall-over from independent trials at four locations. The model performance in terms of bulb dry-matter production was good under environmental conditions close to the optimum, but insufficient under stress situations. The model overestimated leaf area index and green leaf dry matter. Bulb formation was simulated satisfactorily, while the time of 50% fall-over was simulated too early at low plant densities.     

芽孢杆菌在棚室黄瓜育苗上的应用研究

选用地衣芽孢杆菌BH1和枯草芽孢杆菌B006菌株,分别用2种不同的载体处理,应用于棚室黄瓜的基质育苗,根据幼苗的生长情况,选出适宜的浓度.结果表明:在基质中适宜的浓度为106～107 cfu/g,可有效地促进黄瓜基质育苗的出苗率和苗期根系的发育、干物质的积累和叶面积的提高.     

同步叶片修剪对温室番茄干物质优化分配的影响

 研究了同步叶片修剪对温室番茄品种‘Capita’干物质优化分配的影响。结果表明, 在每穗果实数修剪为6个时, 一方面会减少营养生长库强, 显著降低了叶面积指数(LA I) 和植株总干质量; 另一方面有利于干物质分配到果实, 显著提高果实累积干物质分配率, 补偿因植株总干质量降低而引起的果实干质量的降低。在合理增加植株密度时, 同步叶片修剪可以显著提高LA I与单位面积植株总干质量, 从而显著提高单位面积果实干质量。     

Interactions between root-zone temperature and light levels on growth,development and photosynthesis of Lycopersicon esculentum Mill. cultivar ‘Vendor’

Six-week-old tomato plants were subjected to 5 root-zone temperatures, ranging from 12 to 36°C, and 4 light levels in a factorial design. Large increases in shoot dry weight, leaf area and fruit development resulted from soil warming to 24°C when plants were grown under high light conditions. Shoot growth and fruit weight were reduced at 24°C root temperature under low light conditions. Total plant photosynthesis, leaf area index, net assimilation rates and leaf chlorophyll content were related to plant growth and flower development for the various treatments. Our experiments have shown an interaction between root-zone temperature and light levels for greenhouse tomatoes. Soil warming caused large increases in shoot dry weight and fruit development when light was not limiting plant growth, but had deleterious effects on flowering and fruit set under shaded conditions.     

Re-constructing data of leaf area increment in the greenhouse pot chrysanthemum cultivar ‘Lompoc’

A dynamic model was developed for re-constructing data of shoot leaf area increment in pot chrysanthemum. From specified final areas of individual leaves and time of anthesis of the terminal flower, the model can re-construct dynamic growth of each leaf on side shoots using a modified Richards function. In the model, leaf growth is related to a relative time index ranging from zero to unity, where zero is the start of short day treatment and unity corresponds to anthesis of the terminal flower. Experiments were conducted under greenhouse conditions to collect data for parameter estimation, model verification and model validation. An allometric relationship between leaf length and leaf area was used to estimate leaf area non-destructively from leaf length recordings. When compared with the data used for parameter estimation, the model simulations fitted the data with R² values ranging from 0.979 to 0.998. In the validation trial the model showed a tendency of over estimation early leaf growth but could explain variations in the data with R² values ranging from 0.899 to 0.993.     

日光温室基质袋培番茄东西垄向栽培模式研究

在滑盖式现代节能日光温室采用基质袋培方式开展了番茄东西垄向栽培模式研究,通过分析番茄不同垄向栽培的冠层小环境、植株长势、产量、品质指标,探讨日光温室番茄东西垄向栽培模式产量形成影响因素。结果表明:当栽培密度相同时,与南北垄向相比,东西垄向番茄冠层辐射量和冠层空气温度较高。东西垄向EW-4处理(2.9株· m~(-2))、南北垄向SN-1处理(2.9株· m~(-2))和SN-3处理(2.9株· m~(-2))的茎粗、叶面积、叶面积指数及地下部干质量无显著差异。EW-4处理株高比SN-3处理显著提高13.07%;地上部干质量为473.10 g,分别比SN-1和SN-3处理显著降低19.26%和6.86%;平均单果质量和单位面积产量均显著高于SN-1和SN-3处理;果实可溶性固形物含量高于SN-1和SN-3处理。东西垄向不同栽培密度处理中,EW-1处理(2.2株· m~(-2))植株冠层辐射量较高,EW-4处理冠层空气温度较高。EW-5处理(3.3株· m~(-2))的株高和叶面积指数明显高于其他处理;EW-4处理叶面积及地上部干质量较大;EW-1处理地下部干质量显著高于其他处理。产量方面,EW-3处理(2.6株· m~(-2))的平均单株产量和单位面积产量分别为3.68 kg ·株~(-1)和9.57 kg · m~(-2),明显高于其他处理。各处理番茄果实可溶性糖、有机酸、VC含量和糖酸比均无显著差异。通径分析结果表明平均单果质量和平均单株产量对不同垄向袋培番茄单位面积产量有直接影响。综上,在滑盖式日光温室内,基质袋培番茄采用东西垄向栽培时产量高于南北垄向,以东西垄向栽培密度为2.6株· m~(-2)进行生产可得到较高产量。     

氮素肥料在甜菜生产应用中的研究进展

从甜菜氮肥吸收分配规律以及氮肥对甜菜根系生长、根系活力、叶面积及叶面积指数、干物质积累、产量、品质的影响等方面介绍了氮肥在甜菜生长发育过程中的作用。旨在为提高甜菜氮肥利用率以及块根产量、改善甜菜块根品质寻求有效途径。