薄壳山核桃容器苗培育关键技术研究

发布时间：2018-01-09 03:27

本文关键词：薄壳山核桃容器苗培育关键技术研究　出处：《南京林业大学》2016年博士论文　论文类型：学位论文

【摘要】：薄壳山核桃[Carya illinoensis(Wangenh.)K.Koch],为胡桃科山核桃属植物,是世界著名干果、高档木本油料、优质硬阔木材树种,集经济效益、社会效益和生态效益于一身,发展前景广阔,近年来得到了迅速发展。但是当前造林及建园以裸根苗定植为主,成活率低、缓苗慢影响早期效益,严重制约了其种植潜力的彰显;本文对其种子休眠特性、最适容器、基质及控根技术、苗木生长规律、底部渗灌水分管理以及控释肥应用等关键技术进行研究,建立了薄壳山核桃容器苗培育技术体系。主要研究结论如下:1.研究了种壳机械阻碍、内源抑制物质、生理后熟可能导致种子休眠的因素,以及浸种时间、GA3浸种、催芽温度对种子萌发的影响,结果表明:完全剥除、去除胚根端种壳后,种子达到最大萌发率时间由20 d缩短到12 d左右,说明种壳对胚根的伸长具有明显的机械阻碍。种壳夹裂种子第3 d即达到最终吸水率的85%,而完整种子第8 d仅达最大吸水率的84%,说明种壳存在一定的透水障碍。种壳夹裂种子呼吸速率显著高于完整种子;30°C下种子呼吸速率显著高于20°C下的呼吸速率,说明薄壳山核桃种壳存在透气障碍,较高温度下可得到改善。种壳由木质化石细胞层组成,表面存在一定数量的孔洞,是种子与外界进行空气和水分交换的通道,不同品种种子间孔径、分枝和数量的差异,造成了种子透水透气性的不同。薄壳山核桃种壳中含有化感物质,显著抑制杂交狼尾草种子的萌发和幼苗的生长;对自身的萌发也有抑制作用,但需要积累到一定浓度才能表现出来。在0~9 d、50~200 mg/L、20~37°C范围内,延长浸水时间、增加GA3浓度、提高催芽温度,薄壳山核桃种子发芽势提高,但对最终发芽率无明显影响。薄壳山核桃种子不存在胚休眠或生理后熟,不管是采收的新鲜种子,还是干藏后相对含水量较低的种子,或者经过低温层积处理的种子,只要果实成熟,37°C恒温催芽8 d种子发芽率可达90%。2.研究了8种容器种类和规格组合下薄壳山核桃容器苗生长的情况,相关性分析表明,各生长参数呈显著或极显著相关性,单一指标不能反映苗木的生长状况;采用主成分分析和隶属函数值法综合评价认为,生产中可以薄的美植袋作为育苗容器。研究了容器规格、基质配方、切根比例对苗木生长的影响,多因素方差分析表明,3个影响因子具有交互效应,以15 cm×25 cm或10 cm×30 cm(成本更低)容器、体积比3:1的泥炭和珍珠岩基质、胚根长至6 cm时切去1/2的组合,对容器苗生长最好。3.研究了薄壳山核桃1年生容器苗的生长规律,结果表明,苗高生长和地径生长均呈双S形曲线,一年有两次生长高峰,生长具有交替性,高生长集中在生长前期、生长后期以地径生长为主。根系生长也有两次生长高峰,生长初期以主根伸长为主,生长后期以主根增粗、侧根发育为主,且主根伸长总是出现在苗高生长高峰之前。地上部和地下部生长具有密切联系,且具有交替性。研究了叶面喷施、茎干涂抹KT和GA3对薄壳山核桃容器苗增粗效应,结果表明,所有处理均促进了苗木的粗生长,以叶面喷施200 mg/L GA3和50 mg/LKT促进容器苗地径生长和叶面积增大效果最佳;茎干涂抹促长结果显著低于叶面喷施,且随浓度增加侧芽出现伸长和畸形现象。4.研究了薄壳山核桃容器苗的耐水性,结果表明,淹水30 d,薄壳山核桃幼苗叶片开始变黄,出现少量褐色斑点,叶绿体进一步肿胀变圆,嗜锇颗粒数量增加,片层结构开始松散,但无质壁分离现象;而干旱30 d,叶绿体结构完全破坏,大部分细胞器已经破坏溶解,质壁完全分离。研究了底部渗灌技术的应用及适应机制,结果表明,底部渗灌比上方喷灌节水62%,水分利用效率提高193%;苗木的营养生长、光合指标以及养分积累显著提高,苗高、地径分别提高11.7%和41.5%;根系中N增加53.8%、K增加100%,茎干中N增加35.3%、P增加48.3%,叶片中N、P、K分别增加48.7%、117.2%、28.7%。底部渗灌下苗木仍能保持较高水平的根系活力;随苗木的生长进程,根系SOD(超氧化物歧化酶)、POD(过氧化物酶)和CAT(过氧化氢酶)保护酶活性均表现出先上升后下降的趋势,说明苗木通过提高根系中保护酶的活性消除伤害,不断适应根系环境。5.对控释肥处理后薄壳山核桃容器苗生长指标进行主成分分析,并利用隶属函数值法综合评价,6 g/L的APEX19-6-12处理的中苗木综合评价值最高。控释肥处理显著促进了苗木可溶性糖、可溶性蛋白、淀粉的积累和叶绿素相对含量的提高;随着施肥浓度增加营养物质积累增加,但高浓度(10 g/L)的APEX19-6-12处理显著抑制了营养物质的积累、降低了叶绿素相对含量,其中6 g/L的APEX19-6-12处理下苗木营养物质积累和叶绿素相对含量最高。控释肥处理后矿质元素含量和在各器官中的分配规律不同,N(氮)、Ca(钙)含量均与肥料配方和施肥浓度相关,相同浓度下APEX19-6-12处理的苗木营养元素含量高于APEX 14-14-14处理;K(钾)含量仅受控释肥配方影响;Mg(镁)含量则既不受配方影响也不受施用浓度的影响。除了K外,其它三种元素在植株各器官中的分配均不受控释肥配方的影响。
[Abstract]:Pecan [Carya illinoensis (Wangenh.) K.Koch], for Juglandaceae walnut plants, is the world famous fruit, high-grade woody oil, high-quality hardwood timber species, in economic benefits, social benefits and ecological benefits in a broad prospects for development, has been developed rapidly in recent years. But the current afforestation and garden to bare root colonization, the seedling survival rate is low, slow effect of early benefit, seriously restricted the cultivation potential highlight; the dormancy of the seeds, the most suitable container, matrix and root control technology, seedling growth rhythm, the bottom of the irrigation water management and Research on key technology of control release fertilizer application, set up technical system of Pecan seedling cultivation container. The main conclusions are as follows: 1. research on the shell mechanical obstruction, endogenous inhibitory substance, physiological after ripening possible causes of seed dormancy, and seed soaking time, GA3 soaking, germination Effect of temperature on seed germination, the results showed that completely removal, removal of radiculodium shell, the maximum germination time was shortened from 20 d to about 12 d seeds, that kind of radicle elongation shell has obvious mechanical resistance. Shell crack clip third D seeds reach the water absorption rate of 85%. Complete eighth seed d only reached the maximum water absorption rate of 84%, that kind of housing exist certain barriers. A permeable shell clamp crack seed respiration rate was significantly higher than that of intact seeds; the seed rate of breathing under 30 ~ C was significantly higher than 20 DEG C respiration rate and that of pecan shell in high temperature air barrier can be improved. A shell from the wooden fossil cell layer composition, surface voids of a certain number of seeds of air and moisture exchange channel with the outside world, the seeds of different varieties of aperture, difference and number of branches, causing seed permeability Different. Contains Allelochemicals of pecan shell, hybrid Pennisetum significantly inhibited the seed germination and seedling growth; also has inhibitory effect on the germination, but need to be accumulated to a certain concentration can be shown. In 0~9 D, 50~200 mg/L, 20~37 ~ C range, long soaking time, increase the concentration of GA3, improve the germination temperature, pecan seed germination potential increased, but had no significant effect on final germination rate. Pecan seed dormancy does not exist or whether it is physiological after ripening, fresh seed harvesting, or dry storage after the relative water content of lower seed, or after cold stratification of seeds if the fruit is ripe, at 37 C for 8 d germination seed germination rate of 90%.2. of 8 container types and specifications under the combination of Pecan container seedlings growth, the correlation analysis showed that significant or highly significant phase growth parameters The correlation of the single index can not reflect the growth status of seedlings; by using principal component analysis and subordinate function value method evaluation that can thin the plant bag as seedling container production. The container size, matrix formula, root cutting ratio impact on seedling growth, multivariate variance analysis showed that 3 factors have the interaction effect, with 15 cm * 25 cm or 10 cm * 30 cm (lower cost) container, the volume ratio of 3:1 of peat and perlite, radicle length cut 1/2 to the combination of 6 cm, the best.3. container seedling growth of 1 year old container seedling growth rule, pecan research results show that the seedling height growth and diameter growth showed a double S curve, two times a year growth peak, with alternating growth, high growth is concentrated in the early growth stage, growth stage to diameter growth. Root growth also has two growth peak, early growth in root elongation The main growth period to taproot thickening, lateral root growth, and root elongation always occurred before the peak. The height of seedling growth of aboveground and underground are closely related, and has alternate. Of foliar stem, with KT and GA3 thickening effect on pecan container seedlings. The results showed that all treatments promoted the growth of seedlings with coarse, spraying 200 mg/L GA3 and 50 mg/LKT to promote the container seedling ground diameter growth and leaf area increase the best effect; stem smear growth were significantly lower than that of spraying, and with the increasing of concentration of lateral resistance, pecan container seedlings appear elongation and abnormal phenomenon.4. results showed that 30 d of waterlogging, Pecan seedling leaves turn yellow, small brown spots, chloroplast further swollen osmiophilic granules increased, lamellar structure began to loose, but no plasmolysis now Like; while the drought of 30 d, the chloroplast structure was completely destroyed, the majority of the organelles have been destroyed completely dissolved, plasmolysis. On the bottom of infiltration irrigation technology application and adaptation mechanism, results show that the bottom Irrigation irrigation ratio above 62%, the water use efficiency increased by 193%; the vegetative growth of seedlings, photosynthetic indexes and nutrient the accumulation significantly increased, seedling height, ground diameter increased by 11.7% and 41.5% respectively; the root N increased 53.8%, K increased 100%, stem N increased 35.3%, P increased by 48.3%, leaf N, P, K were increased by 48.7%, 117.2%, at the bottom of the 28.7%. irrigation under the seedlings can still maintain higher root activity level with the growth process; seedling, root SOD (superoxide dismutase), POD (peroxidase) and CAT (catalase) protective enzyme activity showed a downward trend after the first rise, that by increasing the root seedlings protection enzyme activity to eliminate the harm, and constantly adapt to the root Department of environmental.5. on the principal component analysis of growth index of Pecan container seedlings of controlled-release fertilizer treatment, and a comprehensive evaluation method of subordinate function value by 6 g/L APEX19-6-12 treated seedlings in comprehensive evaluation value is the highest. The CRF treatment significantly promoted seedling soluble sugar, soluble protein, starch accumulation and chlorophyll relative content increased; with fertilizer concentration increased nutrient accumulation, but high concentration (10 g/L) APEX19-6-12 treatment significantly inhibited the accumulation of nutrients, reducing the relative content of chlorophyll, which APEX19-6-12 6 g/L the accumulation and chlorophyll of seedlings under nutrient content. The highest relative content of mineral elements controlled release fertilizer and distribution the law in different organs in different N (n), Ca (CA) were associated with manure and fertilizer concentration, seedling APEX19-6-12 treatment under the same concentration camp the nutrient content is high In APEX 14-14-14 treatment, K (potassium) content was controlled only by controlled release fertilizer formula; Mg (mg) content was neither affected by formula nor affected by application concentration. Besides K, the other three elements in plant organs were not controlled by fertilizer release formula.

【学位授予单位】：南京林业大学
【学位级别】：博士
【学位授予年份】：2016
【分类号】：S664.1

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