菜薹(菜心)生长动态与花茎形成

早熟品种四九菜心与中熟品种 60天特青菜心两个播期试验表明,早熟品种与中熟品种的生育过程略有不同,但两者鲜质量和干质量增长,叶片与叶面积都逐步增加,净同化率也逐步提高,以花薹形成期增长最多,净同化率较高;生育过程中干物质分配以叶片生长占大部分,至花茎形成时仍占一部分,菜薹占的干物质比例则逐渐增加,采收时占植株干物质的 40 % ~50 %。     

不同播期对大白菜秋早50生长发育及产量的影响

为确定大白菜新品种秋早50秋延后栽培安全播期,在陕西关中地区研究了不同播种期对秋早50生长发育和产量的影响。试验结果表明,在8月25日至9月12日播种,随着播期的推迟,秋早50的生育期延长,叶球宽、球叶数、叶球紧实度和产量指标均下降,9月7日以后播种的下降最为明显,因此,综合考虑产量和采收期,秋早50秋季最晚播期为9月4日。     

茎瘤芥瘤茎增长过程的研究

以茎瘤芥涪杂1号为试材,研究了瘤茎膨大后瘤茎性状的变化过程。结果表明:用Logistic方程y=k(1+e(a+bt)-1能很好地描述瘤茎纵径、横径、鲜样质量、干样质量的增长过程,而菜形指数的变化过程符合二次回归方程)y=a+b1t+b2t2。瘤茎纵径、横径、干样质量、鲜样质量线性增长始期分别出现在膨大后2.1-9.6d、17.8-19.7d、45.7～48.0d、46.0～50.5d,线性增长持续时间分别为61.6-78,1d、56.1～70.6d、32.9～34.8d、31.6～35.2d;增长高峰期出现在膨大后32.9-48.7d、45.8-55.0d、63.1～64.5d、63.5-66.3d,其最大增长速率分别高达每株每天0.17cm(纵径)、0.16cm(横径)、1.05g(Dw)、16.24g(Fw)。播种晚则瘤茎横径线性增长持续时间短,纵径、干鲜质量增长速率低,而菜形指数的变化由慢到快的递增演变为由快到慢的递减。     

Evaluation of turnip-rooted parsley (Petroselinum crispum ssp. tuberosum) for root and foliage production under a warm,Mediterranean climate

Two experiments were undertaken in southern Greece during 2000–2002 in which turnip-rooted parsley was tested for its suitability for cultivation in comparison with locally grown curly-leafed and plain-leafed forms. Plants were harvested when the foliage was acceptable for marketing, rather than on completion of the vegetative cycle, hence root size was relatively small. In year 1, the foliage development of plain-leafed parsley was significantly higher than that of the other two forms, irrespective of sowing date. In year 2, both plain-leafed and curly-leafed parsley produced more foliage than turnip-rooted parsley in the early sowing (November), but not in subsequent sowings (December and February). During both years, root development was higher in turnip-rooted parsley than in curly-leafed parsley, although in the November and February sowings of year 1 the root weight of both plain-leafed and turnip-rooted forms were similar. In all three types of parsley, foliage yield fell off significantly in the spring sowing (February), and in year 1 there was a considerable decrease in root production as well. In most cultivars, foliage weight was higher when plants were grown from transplanted seedlings rather than by direct sowing, whereas the effect of sowing method on root weight was sowing date dependent. Cultivar differences in the foliage weight of direct sown and transplanted plants were reflected by differences in plant height and, in some cases, by leaf number. It is concluded that although overall turnip-rooted parsley produced rather less foliage than that plain-leafed parsley, this was compensated for by the satisfactory production of roots and therefore turnip-rooted cultivars may constitute a suitable crop for introduction to the Mediterranean region.     

品种和播种期对秋莴笋先期抽笋率和产量的影响

对７ 个秋莴笋品种的４ 个播种期进行了比较试验,结果表明先期抽笋与品种和播种期密切相关。阔圆叶品种最不易先期抽笋,长圆叶品种次之,尖叶品种最容易先期抽笋。秋莴笋合适的播种期在８ 月中旬,合适的品种也比较多,若播种期提前到７ 月中下旬,只能选用圆叶品种。     

播种期和品种对早熟花椰菜植株生长及异常花球的影响

对3个早熟花椰菜品种进行播种期试验,调查花球形成时植株的生长情况、从定植到花球开始形成的时间和从定植到采收的时间、异常花球种类和发生率。结果表明,随着播种期的推迟,花椰菜植株在花球形成时的最大叶长、叶宽和株高呈明显上升的趋势,花球开始形成时的叶片数则随着播种期的延迟而呈现下降的态势。播种期对花椰菜从定植到花球开始形成的时间以及从定植到采收的时间有显著的影响。花椰菜平均花球质量随着播种期的延迟而呈现上升的趋势,并于适宜播种期达到最大,之后再次下降。花椰菜异常花球包括毛花球、夹叶球、小球、未结球等类型,其发生率和发生的种类随播种期和品种的不同而发生规律性变化。     

The effect of temperature on growth and development of cultivars of radish under winter conditions

Leaf and root growth and development of 7 early radish cultivars and strains were studied at a series of constant temperatures varying from 10°C to 26°C under winter conditions. Maximum leaf growth was observed at 23°C, maximum root growth initially at 14°C and later on at 10°C. Total dry matter production was highest at 23°C. Between the cultivars/strains distinct differences in rate of leaf and root growth were noted, but no clear interactions of temperature X cultivar/strain were found. The prospects of shortening the growing-period in winter of early radish by means of regulating environmental factors and plant breeding are discussed.     

"K新绿"鲜食大豆夏种播期比较试验

为了研究K新绿鲜食大豆在铜陵地区夏种最迟播种时期，选择6月25日、7月5日、7月15日、7月26日4个播期进行比较试验，结果表明：K新绿鲜食大豆在铜陵地区夏种最晚播种时间在7月上旬，7月5日播种的大豆生育期和植株生长均正常，结荚鼓粒较好，多粒荚率为82.6%，百粒鲜质量最大，为78.6 g，667 m2产量较高，为680.3 kg。建议夏种K新绿鲜食大豆最晚在7月上旬播种，以保证较高产量和收益。     

Effects of Temperature on the Growth of Corchorus Olitorius

Controlled environment experiments were conducted using base-line growth study conditions to evaluate the responses of cvs Angbadu and Yaya of Corchorus olitorius, a tropical leafy vegetable, to day/night temperatures of 25°/20°, 30°/25° and 35°/30°C. Some of the parameters studied were greatest at 35°/30°C and least at 25°/20°C for both cultivars. Dry weights of both cultivars increased with rising temperatures during the first 21 days after emergence, and the greatest leaf area was at 30°/25°C for both. The nearest to the optimum temperature regime for this species was 30°/25°C. Based on leaf area at any temperature, cv Yaya would be preferred, but its superiority over cv Angbadu as indicated by dry weight is due to some extent to its greater stem length which is not composed of nutritionally important tissue.     

Predicting pod quality of green beans for processing

Two field experiments with green bean cultivars (Phaseolus vulgaris L. cv. Alcade, Carlo, Cleo and Mutin) were carried out. In Experiment 1, different plant populations of the Alcade cultivar were used, whereas in Experiment 2, there were different sowing dates with the Carlo, Cleo and Mutin cultivars. Several harvest dates were considered in both experiments. Yield and quality variables of pods that can be used to evaluate quality and maturity were determined (alcohol-insoluble solids, dry matter content, seed: pod ratio, fibre content, length of 10 seeds, Kramer shear press, colour, lipid content and mineral composition). The alcohol-insoluble solids content, dry matter content, seeds: pod ratio, fibre content, and shear press were linearly correlated. Alcohol-insoluble solids content was related with thermal time by exponential equations provided thermal time was calculated from the beginning of flowering and the effect of high temperature on the rate of development was taken into account. The alcohol-insoluble solids content was correlated to the length of 10 seeds by exponential equations, with different parameters for different cultivars. The optimum harvest date, which corresponds to 10% dry matter content and 6.6% of alcohol-insoluble solids, could be set at thermal times after first flowering of 356, 384, 429 and 417 °C d for ‘Alcade’, ‘Carlo’, ‘Cleo’ and ‘Mutin’, respectively.The aim of this study was to fit empirical models to simulate the course of pod quality variables of green beans.     

The emergence and early growth of French and runner beans (Phaseolus vulgaris L. and Phaseolus coccineus h.) sown on different dates

The results are reported of an investigation into the effects of sowing on different dates on the emergence and growth of various cultivars of Phaseolus vulgaris and P. coccineus under field conditions. In 1969 five cultivars of French bean and three of runner bean were sown in the field at fortnightly intervals from April onwards. The experiment was repeated, with the addition of two cultivars, in 1970. Consistent differences were found between and within species for a number of growth parameters.

(1) Especially in the early sowings, seedlings of runner beans emerged before those of French beans, and small-seeded cultivars of French bean (in particular Comtesse de Chambord) before larger-seeded cultivars.

(2) The mean relative growth rates measured after emergence were greater in French beans than in runner beans, but differences within species were not significant. Very early sowing appeared to have a lasting depressive effect on the growth rates of seedlings of both species.

(3) The estimated weights of seedlings at emergence (estimated from regressions of seedling weight on time since emergence and on seed weight) were lower in the early sowings than in later sowings, and especially so in the cultivar Comtesse de Chambord.

The main results in each year were similar, but some differences in detail were found. In particular there were differences between years in the emergence of cultivars as affected by soil temperature. The discrepancies were attributed to a difference in the temperature regimes of the two sites.     

The Response to CO2 Enrichment of Capillary-Watered Single-Truss Tomatoes at Different Plant Densities and Seasons

CO₂ enrichment advanced the date of first anthesis, promoted earlier cropping and shortened the duration of harvest for single-truss tomatoes sown in December and, to a lesser extent, for those sown in July. It also prevented arrested development of the flowers of a December-sown crop growing in poor light.

CO₂ caused increases in marketable fruit yield that were greatest for a mid- July sowing and least for a mid-December sowing. The increases obtained from plants sown in mid-December were independent of population density. For a mid-July sowing the increases in yield of ripe marketable tomatoes were 33% and 17% at population densities of 10 and 25 plants/m² respectively. Increases in total marketable fruit weight caused by CO₂ resulted from an increase in the number of fruits attaining marketable size and an increase in the average weight of individual fruits.

Some of the advantages of producing fruit on single-truss tomatoes grown in shallow capillary-watered beds are mentioned.     

Enzyme activity changes in relation to internal browning of Raphanus roots sown early and late

Summary

Early sown radish seedlings were subjected to heat stress from the middle to late growth stage. Roots exhibiting internal browning (IB) were more prevalent in the susceptible cultivars whose seeds were sown early in the summer compared with those which were sown late. However, IB occurrence in the resistant ones was not nearly so marked regardless of the sowing date. In the IB susceptible cultivars, higher levels of L-phenylalanine ammonia-lyase (PAL) and polyphenol oxidase (PPO) activities were detected in roots from the early sown plot (ESP), but these enyzme inductions did not occur to a significant extent in the resistant ones. Roots suffering internal browning were also detected to have pronounced increases in ascorbate peroxidase (APX) activity, but decreases in both dehydroascorbate reductase (DHAR) and glutathione reductase (GHAR) activities. These observations strongly suggest that a decline in H₂O₂ decomposing capacity of the ascorbate-glutathione cycle by heat stress is responsible for the activation of H₂O₂ detoxyifying pathway derived from PPO.     

晚播加工番茄生育关键期生理生化指标研究

基于新疆加工番茄生长发育规律,设计不同播期处理,第1播期(正常播期)(4月15日)、第2播期(5月15日)、第3播期(6月15日)。在加工番茄不同发育期对各处理进行过氧化氢酶(CAT)活性、超氧化物歧化酶(SOD)活性和过氧化物底物酶(POD)活性等生理生化指标进行测定,以揭示晚播加工番茄生长发育过程中高温胁迫对植株生理生化的影响。结果表明:晚播处理加工番茄叶片SOD活性呈先降低后上升再降低的趋势,清除氧离子速率显著降低;叶片POD活性呈先下降后上升再降低的趋势,与正常期处理对比差异显著;叶片CAT活性呈先下降后上升趋势,与正常播期处理对比也发生较大变化。对各处理产量测定表明,晚播处理的产量显著低于正常播期处理的产量,正常播期处理667m2产量达5.81t,第2播期处理产量为3.51t,第3播期处理产量为1.76t。     

珠三角地区稻后冬闲田直播油菜薹品质分析

为分析珠三角地区冬种油菜的菜薹采摘效益，以油菜“希望669”为材料，在广东江门新会区采用直播方式播种，分析比较不同播期（稻收后15 d和稻收前3 d）下油菜薹宜采期的品质差异。结果表明：不同播期下油菜不同生育时期品质存在显著性差异，均略优于菜心。其中，在油菜初花期之前（春节期间）的宜采期，油菜薹单位面积生物量与油菜薹维生素C、可溶性蛋白含量及叶片SPAD值均表现出稻收前播种优于稻收后，而纤维素含量则相反。在油菜初花期后，油菜薹可溶性糖含量表现为稻收前播种优于稻收后。2个播期下冬种油菜的菜用可采期均与珠三角蔬菜市场短缺期重合；因此，冬种油菜可以调节春节市场油菜薹的有效供给，产生良好的社会和经济效益。     

Heat tolerance in English ivy as measured by an electrolyte leakage technique

Summary

Identification of heat-tolerant English ivy (Hedera helix L.) genotypes for commercial production in hot areas is desirable. The extent to which electrolyte leakage from English ivy leaf discs, measured using a test for cell membrane thermostability (CMT), could be related to the reduction to shoot dry weight induced by heat in the greenhousegrown plants was determined. A curved relationship existed between the relative injury (RI) value occurring in leaf tissue discs of English ivy cultivars and treatment temperature. A single temperature treatment at 50°C resulted in injury values near the midpoint of the response curve and showed the greatest sensitivity in detecting genotypic differences in heat tolerance. The cultivars with a high RI value are those with the lesser CMT and more reduction in shoot dry weights by high day/night temperature at 35/30°C.     

Effect of Leaf Number and Area on the Fruit Growth of Regular and Biennial Bearing Mango (Mangifera indica L.) Grown Under North Indian Conditions

Abstract

The optimum leaf number required for normal fruit growth in the regular bearing mango cultivar ‘Amrapali’ and the biennial bearing cultivars ‘Chausa’, ‘Dashehari’ and ‘Langra’ were studied by isolating individual fruits with known numbers of supporting leaves by shoot girdling at the time of fruit set. There were significant differences in the leaf area (249.01-1817.10 cm2), fresh weight (7.0-77.0 g) and dry weight (3.7-50.0 g) of leaves on shoots having 30, 20, 10 and 5 leaves as compared with control in different cultivars. In both types of cultivars, there was a progressive reduction in fruit size in terms of total fruit, pulp, peel, and seed weight with decreasing numbers of supporting leaves, however, a minimum reduction (2.4%) in fruit growth in ‘Amrapali’ was noticed with 30 supporting leaves. A nonsignificant difference in photosynthetic rate with varying number of leaves was found but its efficiency in leaves was higher in ‘Amrapali’ as compared with biennial bearing cultivars. Starch accumulation in the leaves was reduced by shoot girdling. The stomatal resistance of the leaves of girdled shoots was comparable with that of leaves on control shoots. In all the cultivars except ‘Amrapali’ it was observed that 30 leaves, the maximum retained on a shoot, could not support the growth of a single fruit to normal size. The data on rate of photosynthesis in different pool size of leaves and fruit growth in girdled and nongirdled shoots clearly show that fruit development depends not only on the current assimilates but also to a great extent on reserves. A 14CO2 feeding experiment showed a higher rate of carbon fixation in the leaves of girdled shoots than in the control shoots, but the translocation of 14C assimilated to the developing fruits on the girdled and control shoots was comparable. The results also indicated that developing fruits are major sinks for current photosynthates as more than 60 percent of the 14C exported from the treated leaf was found in the fruit in all instances.     

结球芥菜的生长动态与叶球形成

结球芥菜自播种至叶球采收可分为发芽、幼苗、叶簇生长和叶球形成4个生长期。植株、根、外叶和叶球的鲜样质量和干样质量随生长进程均逐步增加,呈单峰曲线的增长动态。叶球的鲜样质量和干样质量分别占植株鲜样质量和干样质量的48.2%和48.8%,经济系数近0.5。生育过程中,第1~5展叶是培育幼苗和叶簇的功能叶,第5~9展叶则是叶球形成的主要功能叶。叶球形成过程中球叶数及其叶面积和质量均逐步增加,采收时叶球约有12片球叶。球叶的叶面积和质量都由外而内逐渐减少,叶球的大小和质量主要决定于最外面的6片球叶(占球叶面积的84%和叶球质量的85%),属叶重型叶球     

Comparisons of the use of pre-germinated,dry and pelleted seeds for block-raising of glasshouse lettuce

The use of pre-germinated seeds for establishing glasshouse lettuce in peat blocks was compared with dry and pelleted seeds. Sowing pre-germinated seeds gave between 1 and 6% higher seedling emergence than from pelleted seeds and between 1 and 3% higher emergence than from dry seeds. Seedling emergence was reduced from 100% to 56% when the seeds were covered with 5 mm of silver sand compared with no cover. Seedling emergence from seeds covered with Agrigel (sodium alginate) was reduced by 24% at a concentration of 0.25% and by 62% at 0.7% compared with no cover.Guar (a natural gum) and Laponite (a synthetic clay) gels also reduced emergence on certain occasions but not by as much as Agrigel. Satisfactory levels of emergence were obtained when seeds were sown into blocks having an inverted, cone-shaped depression for locating the seeds, but the seedlings showed poor root-hair development and had elongated hypocotyls. Normal seedling growth and high levels of emergence were obtained from the seeds sown into blocks having cylindrical holes 10 mm in depth and 5 or 10 mm in diameter. Pre-germinated seeds invariably emerged earlier than pelleted or dry seeds. At low propagating-temperatures (12.0°C maximum and 5.0°C minimum), emergence was 4 days earlier from pre-germinated than from dry or pelleted seeds and 2–3 days earlier at high temperatures (21.0°C maximum and 9.0°C minimum). Coefficients of variation of seedling weight at planting were lower from sowing pre-germinated than pelleted or dry seeds, but these differences were not evident at harvest.     

紫豇豆“绵紫豇1号”播种期及密度试验

摘要：为研究紫豇豆品种绵紫豇1号的配套栽培技术,为其栽培及推广提供科学依据,进行了6个播种期及3个种植密度的双因子试验,分析不同播种期与密度对绵紫豇1号的生育期、植物学性状和产量的影响。结果表明：对绵紫豇1号豇豆产量的影响顺序依次为播种期＞播种期与密度互作＞密度;产量随播种期的推迟呈下降的趋势,随密度的增大呈先升后降趋势。综合得出,绵紫豇1号在四川地区的适宜播种期为3月25日前后,播种期不宜太迟,太迟会影响产量;在土壤中上等肥力水平下的适宜种植密度为667 m2栽8 100株。