鹧鸪茶扦插繁育技术

以鹧鸪茶木质化或半木质化枝条作为扦插材料,通过对比试验,研究植物生长调节剂、处理浓度、处理时间和插穗剪切方式等对鹧鸪茶扦插生根和移栽存活的影响。结果表明,使用200 mg/L的NAA处理8.0 h以上对鹧鸪茶插穗的生根效果最佳,采用保留3个腋芽和5片叶片的剪切方式对鹧鸪茶插穗的移栽存活较好。     

余庆县太子参叶斑病发生规律及防治技术

为指导太子参生产,2013年对贵州省余庆县太子参叶斑进行了调查.结果表明：太子参叶斑病3月末开始发病,4月上、中旬病株率增长缓慢、发生较轻,4月下旬至5月上旬日病害急增期,病株率、病叶率、病情指数增长较快,5月中旬田间开始出现地上部枯死,6月初由于发病严重导致田间地上部分枯死.温度、湿度、轮作、海拔高度、土壤质地及栽培管理是影响其发生主要因子.防治技术为以农业防治为基础,抓住关健时期、对症用药.     

7种红花槭在北京的生态适应性评价

以7个红花槭品种为研究材料,从物候期、植株生长量、耐热性、耐寒性及抗病虫害能力5个方面,研究了7个红花槭品种在北京地区的生态适应性,并对其作出了综合评价.结果表明:‘仙娜格林'、‘索美赛'、‘酒红'、‘红点'、‘十月光辉'5个品种适应性最强.‘北林'次之,‘太阳谷'抽条较严重,适应性较差,不适于在北京地区栽培.‘索美赛'、‘红点'、‘酒红'、‘十月光辉'秋色叶观赏期最长可达30 d,观赏效果好于其他品种.     

Resource competition across the crop-tree interface in a maize-silver maple temperate alley cropping stand in Missouri

In order to improve the management of temperate alley cropping, it is important to study the growth and physiological responses of plants arising from competition across the crop-tree interface. Maize (Zea mays L.) was established between rows of seven-year-old silver maple (Acer saccharinum L.) trees in north-central Missouri, USA with four imposed treatments: (1) an unmodified control with a standard rate of N fertilization (179.2 kg N (as NH₄NO₃) ha⁻¹), (2) trenching with root barrier installed, (3) supplemental fertilization treatment (standard N + 89.6 kg ha⁻¹ N), and (4) a combination of trenching with root barrier and supplemental fertilization. Whereas soil N status had little effect on maize physiology and yield at the interface, competition for soil water was substantial in both years. Without a root barrier, soil water content, predawn and midday water potential, and midday net photosynthesis of maize plants adjacent to the tree row were reduced compared with those of plants in the alley center, but no differences across the maize crop were evident in the presence of a barrier. Grain yield of border row maize plants lacking an adjacent barrier was depressed compared with that for maize plants with a root barrier present (8.42 vs. 6.59 Mg ha⁻¹ in 1997; 5.38 vs. 3.91 Mg ha⁻¹ in 1998). However, the barrier did not completely restore yield to that in the alley center, suggesting that reductions in light near the tree row also limited production. Top ear height showed a similar pattern of response to the presence of a root barrier. Silver maple trees responded to root barrier installation with reduced annual diameter growth and reduced water status on some sample days. This revised version was published online in June 2006 with corrections to the Cover Date.     

青榨槭外植体消毒方法初步研究

以青榨槭带芽茎段为外植体,研究了取材时间、消毒剂种类以及处理时间对外植体灭菌效果的影响。结果表明,0.1%、0.2%升汞处理5 min或7 min的污染率显著低于1%次氯酸钠处理20 min或30 min;75%酒精浸60 s后,用0.1%的升汞消毒7 min和0.2%的升汞消毒5 min或7 min的处理间没有显著差异,其中75%酒精浸60 s后用0.1%的升汞消毒7 min的消毒效果最好,外植体污染率和存活率分别为1.9%和90.4%。4月中旬至7月中旬取材的外植体污染率均低于5%,而存活率均达90%以上,为青榨槭茎段外植体取材的最佳时期。     

元宝枫叶内黄酮、绿原酸含量动态变化研究

通过对不同月份元宝枫叶产量和叶内黄酮、绿原酸含量的动态研究表明：元宝枫叶内黄酮的含量以8月份最高,含量达5．73％;绿原酸含量以6月份较高,含量最高达4．13％。元宝枫单株叶产量以8月最高,产量达131g。7月份和8月份单株叶内黄酮和绿原酸较高,其中黄酮含量8月份最高,平均每株含7．50g;绿原酸含量7月份最高,平均每株含4．39g。不考虑其它因素情况下,7月份和8月份是采摘元宝枫叶的最佳时期。     

元宝槭幼树施肥研究 Ⅱ .对叶内黄酮、绿原酸及养分的影响

测定9个不同施肥处理下元宝槭叶内黄酮类化合物、绿原酸和N、P、K、Ca、Mg、Fe、Zn、Cu、Mn和B的含量与积累量,通过主成分分析影响黄酮类化合物、绿原酸含量的因子。研究结果表明：N0P250K75和N0P125K37.5处理下元宝槭的黄酮类化合物、绿原酸积累量比对照增加1～1．5倍,是叶用原料林的最佳施肥配方;施肥处理下营养元素的含量与积累量呈正相关,但黄酮类化合物、绿原酸含量与积累量并不呈正相关;“光合与氮素代谢促进”因子和“酶促反应促进”因子是影响黄酮类化合物和绿原酸含量的两个最主要的成分,其变异积累贡献率在87％以上,且以P、Cu、Mg的负荷量最大,可通过调节叶内营养元素的含量对黄酮类化合物和绿原酸的含量进行调控。     

Adaptive responses of<Emphasis Type="Italic">Acer ginnala,Pyrus ussuriensis and Prunus davidiana</Emphasis> seedlings to soil moisture stress

One-year-old seedlings of Amur maple (Acer ginnala Maxim), Ussurian pear (Pyrus ussuriensis Maxim) and David peach (Prunus davidiana Carr) were planted in pots in greenhouse and treated with four different soil moisture contents (75.0%,61.1%, 46.4% and 35.4%). The results showed that net photosynthesis rate (NPR), transpiration rate (TR) and stomatal conductance (Sc) of seedlings of the three species decreased with the decease of soil moisture content, and Amur maple seedlings had the greatest change in those physiological indices, followed by Ussurian pear, David peach. Amur maple and Ussurian pear seedlings also presented a decrease tendency in water use efficiency (WUE) under lower soil moisture content, whereas this was reversed for David peach. Under water stress the biomass allocation to seedling root had a significant increase for all the experimental species. As to root/shoot ratio, Amur maple seedlings had the biggest increase, while David peach had the smaliest increase. The leaf plasticity of Amur maple seedlings was greater, the leaf size and total leaf area decreased significantly as the stress was intensified. No significant change of leaf size and total leaf area was found in seedlings of Ussurian pear and David peach. It was concluded that Amur maple was more tolerant to soil moisture stress in comparison with David peach and Ussurian pear.     

Prescribed burning and hexazinone herbicide as release treatments in a sapling hardwood-loblolly pine stand

To compare release treatments, a randomized complete block study was established in a 7-year-old hardwood-loblolly pine (Pinus taeda L.) stand in central Louisiana established using chopping and burning. There were 5 blocks of 3 treatments each: (1) check, (2) hexazinone applied once, and (3) prescribed backfiring applied twice. The first burn in December 1985 (7 years after site preparation) had a fire intensity of 90 kJ/s/m. The hexazinone herbicide was applied in April 1986 (the 8th year after site preparation) with a metered spotgun applicator at a rate of 3.0 kg active ingredient/ha. The second burn in March 1989 (the 11th year after site preparation) had a fire intensity of 106 kJ/s/m.The two prescribed burns increased the number of stems less than 1.5 m tall from 1,380 to 2,960/ha red maple (Acer rubrum L.), blackgum (Nyssa sylvatica var. bifora), and sweetgum (Liquidambar styraciflua L.). Burning reduced the number of loblolly pines less than 2.0 m tall, which resulted in a significant increase in average loblolly pine height and diameter. Loblolly pine comprised 62 and 59% of the basal area on the check and burn treatments, respectively, 11 years after site preparation. Hexazinone reduced the number of blackgum, sweetgum, and oak (Quercus spp.) from 6,100 to 4,560 stems/ha and resulted in significantly less hardwood tree basal area than found on the check or burn treatments. Therefore, the herbicide treatment resulted in principally a loblolly pine stand (over 80% of the total tree basal area was pine) four years after hexazinone application.     

马尾松、糖槭种子成分分析和利用

分析了马尾松 (PinusmassonianaL .)和糖槭 (AcernegundoL .)种子的化学成分。试验结果表明 :(1)不同树种及同一树种不同部位的化学成分含量不同 ;(2 )马尾松种子贮藏物质以脂肪为主 ,蛋白质次之 ;(3)糖槭种子以蛋白质为主 ,脂肪次之 ;(4 ) 2树种油脂中均以不饱和脂肪酸 (油酸、亚油酸 )为主 ;蛋白质组成主要以谷氨酸、精氨酸、天门冬氨酸、亮氨酸为主 ;(5) 2树种种子中含有丰富的VE,并有一定的营养价值