Gkowth and Flowering of the Tomato in Relation to Natural Light Conditions

Continuous-recording photometers were used to measure the amounts of light entering a glasshouse during certain growth periods of young tomato plants. Fresh and dry weights of the tops of the plants and the number of days between cotyledon expansion and anthesis of the first flower of the first inflorescence were related to the recorded light values as follows :

1. The relationship between log dry weight and the light-time integral was linear up to 220,000 foot candle hours, after which a marked reduction in growth occurred.

2. The departure from linearity occurred at about the same light integral even when additional nutrients were supplied to the standard volume of compost, but was delayed when a larger container was used.

3. The number of days to anthesis and the recorded light-time integrals show the following relationships : in winter, light integrals are constant (about 400,000 f.c.h.) while time is variable ; in summer, time is constant (about 40 days) while the light integrals are variable.

4. In summer, neither the reduction of the natural day-length to 9 hours nor the reduction of the light intensity to 75% normal materially influenced the number of days to anthesis.

It is concluded that in winter growth is limited by, and is therefore proportional to, the amount of available photosynthetic light, while in summer the young tomato is light-saturated and growth is limited by factors other than light.

The results indicate that the amount of photosynthetic light is the major factor determining the seasonal pattern of days to anthesis. There was no indication of any photoperiodic response.     

Damage to Leaves Caused by Fruit Tree Red Spider Mite,Panonychus Ulmi (Koch)

Fruit tree red spider mites, Panonychus ulmi (Koch), were caged on the upper or lower surface of plum or apple leaves; the speckles resulting from their feeding were visible only from the surface on which they fed. Histological studies revealed that mites on the lower surface do not damage the uppermost layer of palisade mesophyll cells. Mites on both surfaces at first feed predominantly on tissues close to the veinlets, damaging mesophyll and bundle sheath cells. Bronzing, which develops later, is associated with damage to mesophyll cells further from the veinlets. Larger speckles are seen when mites have fed on leaves when they were still expanding, causing cells adjacent to those directly damaged to develop abnormally, and the leaves are distorted locally; in some cases a phellogen is formed.     

桂味荔枝不同枝梢类型与开花结果的关系研究

桂味是典型的难于丰产稳产的荔枝品种之一,其主要原因是：易发冬梢,常常“有花无果”且大小年现象严重.笔者通过连续5年对桂味荔枝的枝梢特性观察和相关试验,为解决桂味荔枝着果难问题找到了切实可行的途径和方法.     

晚栽洋葱鳞茎栽植密度对种株生长及种子产量和质量的影响

以"莱农5号"洋葱为试材,于11月28日栽植洋葱鳞茎,设每667m2栽植3 700株(T1)、4 400株(T2)、5 000株(T3)、6 000株(T4)4种栽植密度处理,探讨不同栽植密度对洋葱种株生长及种子产量和质量的影响。结果表明:在种株营养生长、生殖生长、种子质量的测定指标中,T1、T2、T3各指标差异不明显,T4各指标与T1、T2、T3差异显著,发病率较高;在种子产量方面,T3产量较高,分别比T1、T2、T4增产23.03%、14.41%、50.28%。因此,晚栽的洋葱鳞茎栽植密度以T3处理,即每667m2栽植5 000株为宜,栽植密度过大、过小都达不到产量高、品质好的目的。     

The Effect of Cold Storage and Treatment with Gibberellic Acid on Flowering and Bulb Yields of Dutch Iris

Iris bulbs of the varieties Wedgewood and Prof. Blaauvv were injected with 50 or 500 μg. gibberellic acid (GA) before or after cold storage (10° C.) of 18 or 35 days. GA injection accelerated flowering by up to 19 days ; it had little or no effect on length of leaves or flower stem. It was most effective when applied at an early stage after flower initiation.

GA injection reduced bulb yield of Wedgiwood plants, and had no effect on, nor increased bulb yield of, Prof. Blaauw plants.

GA spraying (seven times at 10^-2M of GA) accelerated flowering and increased foliage growth in both varieties. It increased flower stem elongation and reduced bulb yield in Wedgfcwood plants.     

东方百合鳞茎长期冷藏期间形态和生理变化研究

以浙江省山地自繁的东方百合鳞茎'索蚌'(Sorbonne)为试材,探讨了5℃冷藏条件下鳞茎的芽伸长变化,以及贮藏性和代谢性养分的变化规律.结果表明:百合鳞茎内的新芽在冷藏过程中不断伸长,60 d后顶芽生长点距鳞茎端部的距离小于1 cm,继续冷藏1个月后新芽突破顶端.在贮藏的前2个月,淀粉含量明显下降,外层鳞片是3层中下降幅度最大的,后2个月淀粉含量趋于缓慢上升.可溶性总糖和蔗糖含量在贮藏的5个月时间里,均呈不断上升的趋势.中层鳞片的可溶性总糖含量增幅最大,达到了196.11%.     

贮藏条件对彩色马蹄莲种球生长和开花的影响

球茎萌芽率与贮藏温度正相关,且品种间差异明显,在6℃和12℃贮藏8周后,"黑眼睛"萌芽率分别为45.9%和49.2%,"佳人"萌芽率分别为27.9%和50.0%.开花数随贮藏时间延长而减少,"黑眼睛"种球12℃贮藏8周,12周,16周开花数最多,"佳人"种球12℃贮藏16周开花数最多.     

“三薹”育种研究报告(1985-2014)

自1985-2014年育成一批红菜薹、菜心雄性不育系及其保持系,并用不育系配成一批红菜薹、白菜薹及菜心等杂交种,育成菜心、白菜薹、红菜薹新品种共9个,极大丰富了这3种薹用不结球白菜的品种,现将其育种研究过程总结发表,希望对育种工作者有参考价值。     

林芝黄牡丹种子育苗及生长开花特性观测

对原产西藏林芝地区的野生黄牡丹种子进行育苗试验,并对其生长及开花特性进行观测,得出以下结论：林芝野生黄牡丹在甘肃兰州地区生长情况良好,植株特性与原产地基本一致;利用野生牡丹种子进行人工处理育苗,解决了种子野外自然繁育能力低的问题;采用室内装有河沙的花盆进行种子育苗,出苗后及时移栽到大田,大大地缩短了林芝黄牡丹的首次开花时间。     

东方百合鳞茎冷藏解除休眠的养分代谢和酶活性变化

 以自繁的东方百合鳞茎为材料, 研究在2℃、5℃和8℃条件下, 鳞片中淀粉、可溶性总糖、还原糖含量和几种酶活性的变化。在8周的冷藏期内, 淀粉含量持续明显下降, 可溶性糖和还原糖含量增加, CAT、POD、SOD酶的活性在冷藏第1周下降极显著, 而α - 淀粉酶活性在第3周出现峰值, 自冷藏第4周后4种代谢酶活性均处于低水平。本试验中, 不同低温处理间的差异不大, 冷藏第7周后可解除休眠。     

柑橘幼果发育期碳水化合物代谢及其与生长发育的关系

温州蜜柑幼果在盛花后逐渐生长 盛花后6 d开始大量脱落 日本甜夏橙幼果在盛花后12 d内重量未增加，一直处于急剧落果期。甜夏橙幼果中蔗糖含量高出温州蜜柑20多倍，种间还原糖含量变化趋势略有不同。两种柑橘的淀粉含量变化也不同，但它们的淀粉含量与淀粉酶活性、幼果相对脱落率均呈负相关。对幼果碳水化合物代谢与生长、脱落的关系作了讨论。     

过量磷对菜心植株生长和产量及品质的影响

采用营养液水培法,研究过量磷对菜心(Brassica parachinensis)植株生长、产量和品质的影响.结果表明:与正常磷浓度处理(1 mmol/L H2PO4-)比较,3～7mmol/L H2P04-处理植株生物量和产量均显著降低,5和7 mmol/L H2PO4-处理植株根冠比显著增加;随着磷浓度的增加,菜薹表皮花色苷含量和菜薹可溶性糖含量逐渐增加,菜薹硝酸盐含量逐渐降低,三者与营养液磷浓度均呈显著线性关系.     

Growth of the Strawberry Plant in Relation to Nitrogen and Phosphorus Nutrition

Strawberry plants were grown in conditions producing moderate or severe deficiencies of phosphorus and nitrogen, and the effect on leaf growth assessed in terms of weight and area increases, and the number and size of their constituent cells. Deficiency of both phosphorus and nitrogen reduced the rate of leaf production. Decreased leaf areas were due almost entirely to lower cell numbers and, to a lesser extent in severe deficiency, to smaller cells. The rate of cell production was markedly reduced by phosphorus and nitrogen deficiency, but continued until maximum leaf area was attained, increases in mean cell size having ceased earlier. There was no nutritional effect on cell number or cell size before leaf emergence and it is suggested that the rapid divergence of response thereafter may be related to photosynthetic development after emergence.

The effect of phosphorus and nitrogen deficiency on potential fruit yield was confined to the inhibition of branch crown proliferation and the lack of available sites for flower initiation. There was no effect of nutrient level on the number of flowers initiated on each apical meristem. Results suggest that any manipulation of nutrient status aimed at increasing fruit yields should be predominantly concerned with increasing branch crown formation, thus providing additional sites for flower initiation.     

水杨酸诱导提高香蕉幼苗耐寒性的机制研究

 摘要：香蕉幼苗经水杨酸(Salicyhc acid，SA)常温(22/15℃)预处理(0.3—0.9 mmol·L^-1 )1 d可显著降低7℃低温胁迫造成的膜内电解质泄漏，减少5~C低温引起的萎蔫面积，提高抗寒性。低浓度sA预处理(≤0.1 mmol·L^-1 )降低电解质泄漏效果不明显，而高浓度sA(I>2．5 mmol·L^-1 )则增加了电解质泄漏，加剧了低温伤害。0．5 mmol·L^-1 SA常温处理1 d对叶绿素荧光参数(Fv/Flm、Fv’/Fm’、qe、 PSⅡ等)和光合速率(Pn)产生抑制，但效果未达到显著水平；SA预处理可明显减缓低温胁迫期间Fv/Fm、Fv’/Fm’、qP、西eSlI和Pn的下降程度，抑制F0及NPQ快速上升，加快这些参数在恢复期间(22/15℃)的恢复程度，表明sA预处理在低温胁迫期间对香蕉幼苗的细胞膜和一些光合功能提供了保护作用。     

长期增施CO2对蝴蝶兰生长与开花的影响

研究了长期（240 d）增施CO2（800 ± 50）μmol ? mol-1和大气CO2浓度约400 μmol ? mol-1（对照）对蝴蝶兰‘内山姑娘’净CO2吸收速率、生长和开花的影响。结果表明：蝴蝶兰属CAM植物类型,叶片净CO2吸收速率在22：00左右达到最大值,可滴定酸的积累在6：00左右达到顶峰。增施CO2显著提高蝴蝶兰夜间的净CO2吸收速率,并达到对照的两倍,可滴定酸的积累比对照增加44%。蝴蝶兰生物量的积累在增施CO2条件下也显著增加,植株干样和鲜样质量分别增加31%和28%。此外,增施CO2使蝴蝶兰的花期提前了5.4 d,提高了蝴蝶兰的产量和花部品质,其中花朵数比对照增加了66%。     

Physiological and Anatomical Studies of surface Pitting of Sweet Cherry Fruit in Relation to Bruising,Chemical Treatments and Storage Conditions

Mechanical injury of sweet cherry fruit causes the disorder ‘surface pitting’, in which skin depressions overlie necrotic lesions in the fleshy mesocarp. Storage at temperatures near 0°C or the transfer of fruit from cool storage to room temperature worsened the disorder. Pretreating the fruit before cool storage with antitranspirant or surface-active agents exacerbated the disorder, but these effects were mitigated by the addition of CaCl₂. Low O₂, high CO₂ and high humidity atmospheres did not affect the disorder, and low pressure storage was beneficial.     

Ca~(2+)与苹果花粉萌发和花粉管生长的关系

以苹果的花药、花粉为试材,观测Ca(2+)与花粉萌发和花粉管生长的关系。结果表明,不同品种和花芽萌动期的花药中Ca(2+)含量与花粉萌发率和花粉管长度无明显的相关关系。花粉培养过程中花粉壁渗出的Ca(2+)量与萌发率和花粉管长度呈极显著正相关。10(－4)mol·1(－1)的游离Ca(2+)最有利于花粉萌发,1mmol．1(－1)EGTA对花粉萌发和花粉管生长的抑制作用强于0．1mmol．1(-1)．外源CaCl2、Ca（NO3）2、SrCl2在低浓度时对花粉萌发与花粉管生长的作用不大;高浓度时具抑制效应,并且在同等浓度时,SrCl2的抑制作用最大。     

The Irrigation of Early Summer Cauliflower in Relation to Stage of Growth,Plant Spacing and Nitrogen Level

A group of small farms near Ibadan provided data on the annual yields of 2,480 cocoa trees for 18 years. These were entered on punch cards.

The correlation coefficient r (p, i, q) was calculated for the mean yields of units for an earlier period of p years and a later period of q years separated by an interval of i years. The units taken were single trees, one-thirtieth-acre plots and whole farms.

For all units r (1, i, 1) tends to decrease as i increases; but for single trees when i = 0 (and to a lesser extent when i = 2 and 4) it lies below the fitted curve for odd values of i. This is evidence of biennial bearing.

For plots and whole farms r was calculated for every combination of p = 1 or 2, q = 1, 2, 4 or 8, and i up to the maximum possible for each (p, q) combination for all possible years. The values obtained indicate that:

(a) One year’s pre-recording lessens the error variance of the first experimental year on average in the ratio of 0-5 : 1.

(b) The decrease is less for subsequent experimental years, the ratio being about 0-9 : 1 for an 8-year interval.

(c) The error variance of the mean yields over periods immediately following one or two years’ pre-recording is, after adjustment for pre-recording, mainly independent of the length of the period.

(d) Gain in accuracy from two years’ pre-recording is greater than from one, the difference generally more than justifying the cost of the extra year’s recording. But the extra pre-recording which delays the start of an experiment for a further year is not likely to be worth while.