单株留芽量及结果母枝剪留长度对猕猴桃结果性能的影响

对栽植株行距3m×4m的美味猕猴桃秦美品种连续进行了3年试验,单株分别剪留250、300、350、400个芽处理后,平均单株新梢数、叶面积指数、落叶率与留芽数量呈正相关,叶幕下层的光强度、净光合率与留芽数量呈负相关;单株果枝数、果实数及单位面积产量均以留400芽处理最高,但平均单果重最小,88g以上的优质果产量最低。综合评价以单株剪留350个有效芽的效果最佳,优级果产量达到2102.7kg/666.7m2。结果母枝分别剪留7、12、17个有效芽处理后,平均每母枝的结果枝数、果实数、产量与留芽数量呈正相关,均以17芽处理最高,分别达到9.5个、30.4个和3.09kg,各处理间的单果重差异不显著。     

Effects of plant growth promoting rhizobacteria (PGPR) on yield,growth and nutrient contents in organically growing raspberry

During 2003 and 2005, plant growth promoting effects of two Bacillus strains OSU-142 (N₂-fixing) and M3 (N₂-fixing and phosphate solubilizing) were tested alone or in combinations on organically grown primocane fruiting raspberry (cv. Heritage) plants in terms of yield, growth, nutrient composition of leaves and variation of soil nutrient element composition in the province of Erzurum, Turkey. The results showed that Bacillus M3 treatment stimulated plant growth and resulted in significant yield increase. Inoculation of raspberry plant roots and rhizosphere with M3 and/or OSU-142 + M3, significantly increased yield (33.9% and 74.9%), cane length (13.6% and 15.0%), number of cluster per cane (25.4% and 28.7%) and number of berries per cane (25.1% and 36.0%) compared with the control, respectively. In addition, N, P and Ca contents of raspberry leaves with OSU-142 + M3 treatment, and Fe and Mn contents of the leaves of raspberry with M3 and OSU-142 + M3 applications significantly improved under organic growing conditions. Bacterial applications also significantly effected soil total N, available P, K, Ca, Mg, Fe, Mn, Zn contents and pH. Available P contents in soil was determined to be increased from 1.55 kg P₂O₅/da at the beginning of the study to 2.83 kg P₂O₅/da by OSU-142, to 5.36 kg P₂O₅/da by M3 and to 4.71 kg P₂O₅/da by OSU-142 + M3 treatments. The results of this study suggest that Bacillus M3 alone or in combination with Bacillus OSU-142 have the potential to increase the yield, growth and nutrition of raspberry plant under organic growing conditions.     

Influence of growth conditions on yield,quality and diseases of strawberry (Fragaria x ananassa Duch.) var Ofra and Chandler under mid hills of Sikkim Himalaya

Field experiments were conducted during 2005–09 at ICAR Sikkim Centre, Tadong, East Sikkim, India at an altitude of 1400 m amsl to identify the suitable environment for high production of good quality fruits with less diseases for strawberry varieties Ofra and Chandler. Both the varieties were grown under low cost polyhouse, plastic tunnel and open conditions. Maximum number of flower trusses per plant was recorded in Chandler under open condition (13.0) followed by plastic tunnel (12.7). The maximum number of fruits per inflorescence was found in Ofra (7.12) under polyhouse while maximum number of runners per plant was observed in Ofra (12.3) in open conditions. Plastic tunnel with Ofra produced highest fruit weight (26.2 g), fruit length (5.5 cm) and fruit diameter (3.9 cm). Best fruit quality in terms of TSS (6.8%), lower acidity (0.83%) and total sugar (6.3%) was observed in Chandler under plastic tunnel conditions. The highest total fruit yield was recorded with Ofra under plastic tunnel (40.2 t/ha) but the maximum marketable yield was obtained in Chandler under plastic tunnel (35.3 t/ha). Diseases were found to be less prevalent in tunnel as compared to polyhouse and open conditions.     

Split root fertigation enhances cucumber yield in both an open and a semi-closed greenhouse

We investigated the hypothesis that split root fertigation (SRF) approach could provide complementary benefits over traditional fertigation (TF) in terms of water use, vegetative growth and yield formation in the high radiation season and under two atmospheric conditions in a greenhouse. Plants of cucumber (Cucumis sativus L. cv. Cumuli) were grown in a traditional high-wire cultivation system in a peat growing medium. In the SRF method the root system of a plant was separated into two compartments over the crop cycle. One compartment received fertigation solution with low EC (1.2 dS m⁻¹) and the other compartment solution with high EC (3.5 dS m⁻¹) value. In the TF method the EC value of fertigation solution was 2.4 dS m⁻¹. The atmospheric conditions included an open (ventilated) and a semi-closed (cooled) greenhouse. The employment of cooling resulted in an enhancement of the average CO₂ in a semi-closed (810 ppm) over an open (530 ppm) greenhouse resulting in a yield improvement (37%). SRF improved water uptake in both atmospheric conditions and water use efficiency (WUE) in an open greenhouse. The water uptake in SRF was highest in the root part with the low EC values, namely 61% in the open and 66% in the semi-closed greenhouse. In both atmospheric conditions, SRF decreased flower abortion, leading to an improved fruit set with a small effect on vegetative growth. SRF increased yield by 21% in the open and 17% in the semi-closed greenhouse compared to TF in corresponding greenhouses.     

Cane Morphology and Anatomy Influence Freezing Tolerance in Vitis vinifera Cabernet franc

In 2014 and 2015, Ohio vineyards were exposed to multiple freeze events of –20 °C or lower, resulting in vine dieback, i.e., complete damage of above ground parts in Vitis vinifera. Grapevines that sustained dieback were rehabilitated for trunk replacement by training 1-year-old shoots with two distinct morphologies, based on internode diameter of large (L) and normal (N). This study evaluated the impact of cane morphology (L and N) in V. vinifera Cabernet franc on freezing tolerance (FT) of bud, phloem, and xylem tissues in relation to their respective anatomical structures and carbohydrate concentrations. Compared to N canes (7–9-mm diameter), L canes (10–15 mm) in Cabernet franc were considered vigorous and had the following morphological characteristics: long and heavy, with long and wide internode, and presence of numerous laterals. Furthermore, cane anatomy was also different with L canes having a significantly higher number of vascular transport units, xylem vessels, and phloem fibers than those in N canes. Freezing tolerance of buds and phloem was also different between the two cane types, with L canes being more cold sensitive than N canes, especially during fall acclimation and late-winter deacclimation. Sugar concentrations, however, were not different between L and N canes. These results suggest that cane morphology and anatomy play a significant role in affecting FT and the large and abundant anatomical structures of phloem and xylem contributed to the reduced FT of these tissues. In all practicality, this study suggests the best cultural practice for trunk replacement, and vine recovery should include the removal of the undesirable vigorous and cold sensitive canes during pruning.     

Effects of Shelter from Wind on the Growth and Yield of Raspberries

Shelter screens of 63% permeability, erected at right angles to the prevailing wind, gave increases in growth and yield of raspberries (Rubus idaetis). In the year of establishment the total length of cane produced in the region extending from the screens to a distance 3 times their height (0–3 h) was 30% higher than that in the exposed plots. In the following fruiting year yields at the same point were increased by almost 40% by shelter. Corresponding figures for the next year’s cane growth and the second fruiting year were 23% and 16% respectively. Mean wind speeds during the period of the experiment were 1.7 m/sec and 1.2 m/sec for the exposed and sheltered plots respectively, measured at a point 45 cm above the top of the crop, at a distance of 2 h from the screens.

The yield responses appeared to reflect differences in size of the fruiting framework resulting from differences in vegetative growth. There was no evidence of direct physical damage due to exposure.     

Effects of greenhouse cooling method on growth,fruit yield and quality of tomato (Solanum lycopersicum L.) in a tropical climate

A tomato (Solanum lycopersicum L.) crop was grown in four greenhouses during the dry season 2005/06 in Central Thailand. Sidewalls and roof vents of two greenhouses were covered with nets and these greenhouses were mechanically ventilated when air temperature exceeded 30 °C (NET). The other two greenhouses were covered with polyethylene film and equipped with a fan and pad cooling system (EVAP). Overall mean air temperature was significantly reduced by 2.6 and 3.2 °C (day) and 1.2 and 2.3 °C (night) in EVAP as compared to NET and outside air, respectively. Temperature maxima in EVAP averaged about 4 °C lower than in NET and outside. The relative humidity was around 20 and 30% (day) and 10 and 15% (night) higher in EVAP than in NET or outside, respectively. Vapour pressure deficit averaged 0.25 kPa in EVAP, 1.03 kPa in NET and 1.48 kPa outside. The crop water-consumption was significantly lower in EVAP (1.2) than in NET (1.8 L plant⁻¹ day⁻¹), which is ascribed to reduced transpiration in EVAP. Total fruit yield was similar in NET (6.4 kg plant⁻¹) and EVAP (6.3 kg plant⁻¹). The quantity of undersized (mostly parthenocarpic) and blossom-end rot (BER)-affected fruits was reduced in EVAP. However, the proportion of marketable yield was significantly higher in NET (4.5 kg plant⁻¹) than in EVAP (3.8 kg plant⁻¹), owing largely to an increased incidence of fruit cracking (FC) in EVAP. Higher FC but lower BER incidence coincided with higher fresh weight and Ca concentration in the fruits in EVAP. It is concluded that in regions with high atmospheric relative humidity evaporative cooling without technical modifications allowing dehumidification will not improve protected tomato production.     

A reevaluation of alternate bearing in pistachio

Studies documenting pistachio fruiting patterns (Pistacia vera L.) conclude this species shows evidence of alternate bearing; fruit production fluctuates between an ‘on’ year of high yields and an ‘off’ year of low yields. However, alternate bearing in pistachio has never been statistically tested. We collected yields of 4288 trees over six years to test for alternate bearing in a mature orchard planted with ‘Kerman’ scions grafted onto P. integerrima rootstock – the combination planted on the bulk of the acreage in California. A majority (58%) of the trees exhibited statistically significant alternate bearing patterns. Yet 42% showed yield patterns that were indistinguishable from random fluctuations, the standard measure of alternate bearing (I) was only modest (mean I = 0.48), and I varied considerably among trees (range = 0.04–0.83). These findings support that pistachio shows alternate bearing behavior but suggest alternate bearing is less ubiquitous and fruiting patterns are more complex than previously suspected. The presence of such a diversity of yield dynamics creates considerable challenges for crop management and research.     

Morphology of papaya plants derived via anther culture

This study was set up to investigate the morphological and fruiting characteristics of anther derived triploid papaya and evaluate their usefulness in commercial fruit production and breeding. A commercial diploid dwarf cultivar, ‘Wonder blight’ and 26 anther derived papaya strains were raised in the same green house. Data were collected on their morphological and fruiting characteristics like trunk height, fruiting height and the sizes of leaves, flowers and fruits. The anther derived papaya strains were variable in height and could be classified into dwarf, semi dwarf and tall. All the anther derived papaya strains bore only female flowers and produced fruits parthenocarpically. Parthenocarpic ability was variable among the strains. The dwarf and semi dwarf strains were fewer than the tall strains and they had good bearing and high yield of fruits. Two dwarf strains particularly produced parthenocarpic fruits that weighed an average of 670.0 and 871.3 g, compared to the diploid cultivar, ‘Wonder blight’, whose fruits weighed 696.4 g. The combination of short stature with a high yield of large fruits means that these strains have a lot of potential for exploitation in both breeding and commercial fruit production.     

极早熟辣椒新品种博辣娇红的选育

博辣娇红是以SF-11为母本、H2887为父本配制的一代杂交组合。该品种极早熟,第一花节位7~8节,果实羊角形,青果浅绿色,果长20㎝左右,果宽1.3㎝,平均单果质量12g左右,果表光亮微皱,皮薄,味辣,风味好;早期产量为1100㎏/667m2左右,总产量2500㎏/667m2左右;果实红熟快,海南地区从播种到采收红椒约70d;连续坐果能力强,早熟不早衰;抗炭疽病、疫病、病毒病;适于嗜辣地区作极早熟大棚或露地栽培、秋延栽培,辣椒果实可鲜食、加工、干制。     

Cane and bud number effect on yield components of non-irrigated grapes cv. ‘Yaghooti’

An experiment was conducted with non-irrigated vines (Vitis vinifera), in which the number of buds per cane and the number of canes per vine were varied. With increasing canes per plant the percentage bud-burst decreased. Cluster number and total yield increased with increasing the number of buds per vine. Cluster weight and sugar content decreased when vines were overloaded. Yield was positively correlated with cluster number and negatively correlated with sugar content. The position of the pruning-cut affected the percentage bud-burst only near the cut.     

The Response of Malling Jewel And Malling Exploit Raspberries to Different Soil Moisture Conditions and Straw Mulching

The raspberry varieties Mailing Jewel and Mailing Exploit were used to study growth and crop responses to mulching and irrigation from 1957 to 1962 inclusive.

Treatment A consisted of a wheat straw mulch applied deeply enough to form a complete surface cover; treatments B and C of water applications on unmulched cultivated soil at soil moisture tensions of 20 cm. and 50 cm. of mercury respectively, measured at 1 ft. depth. Treatment B was changed after i960 to a single 2-in. water application given when the raspberry fruits began to ripen. Plots under treatment D were cultivated, unwatered and unmulched.

Irrigation greatly increased the rate of cane growth but this was found to be a disadvantage in raspberries grown as continuous rows because the new cane tended to chafe and obscure ripe berries. Restricting irrigation to the pre-picking period reduced height growth but did not appear to reduce cane numbers or crop yield. Crop yield was increased by irrigation to about 30% more than was produced on the unwatered and unmulched plots, mainly as a result of increased berry size, but the full effect of irrigation on yield was not realized because cane numbers and height were restricted. Under the conditions of this experiment, in which the canes were thinned to a given density and tipped to a given height, a single 2-in. application of water at the commencement of ripening, i.e. when the berries showed the first tinge of pink, was a very economic irrigation treatment. Irrigation slightly delayed ripening, probably because of the harder tipping required by the irrigated canes.

The mulch conserved the equivalent of 2 in. of moisture and was intermediate in effect between the irrigation treatments B and C and treatment D in height growth, crop yield and berry size, but had a depressing effect on the production of new canes by the weaker-growing variety Mailing Jewel.     

Effects of defoliation on fruit growth,carbohydrate reserves and subsequent flowering of ‘Hayward’ kiwifruit vines

A partial defoliation study was carried out on ‘Hayward’ kiwifruit vines with the aim of evaluating effects on fruit yield, changes in concentration of carbohydrates, and return bloom. At full bloom, ‘Hayward’ kiwifruit vines trained to the pergola system were submitted to 0% (control), 50% and 75% defoliation in the 2.0 m wide central horizontal area of the canopy. This area represents the vine ‘replacement cane zone’ (RCZ), whereas the remaining external area represents the ‘fruiting zone’ (FZ). Removing 50% of the leaves resulted in a small (−9 g in the RCZ and −3.3 g in the FZ), but significant, reduction in fruit weight compared to the control vines. More severe defoliation (75%) reduced fruit weight by 13 g in the RCZ and 7 g in the FZ. The defoliation treatment reduced the concentrations of starch and total soluble carbohydrates (glucose + fructose + sucrose) in the shoots and starch in trunk bark compared to those in control vines. The treatments caused a large reduction in return bloom, expressed as number of flowers per winter bud, by about 25% and 53% in vines with 50% and 75% defoliation, respectively.     

Assessment of morphological changes and determination of best cane collection time for 140 RU and 5 BB

This study was carried out to assess morphological changes in the canes of 140 Ru and 5 BB and to determine best time for cane collection. The first part of the study included the morphological assessment of the rootstock canes during the winters of 2003–2004 and 2004–2005. Canes collected in the second part of the study in 2005–2006 were grown in pots to relate the changes with the vegetative growth characteristics.     

Effects of oxygen-enriched nutrient solution on greenhouse cucumber and pepper production

A series of experiments were conducted with greenhouse cucumber and pepper plants to determine the effects of oxygen enrichment of the irrigation water on yield and fruit shelf-life. The experiments were carried out in soilless culture in research greenhouses. Depending on the experiment, treatments included sub-ambient (2 mg L⁻¹), ambient (5–6 mg L⁻¹), medium (16 mg L⁻¹) and high (30–40 mg L⁻¹) levels of oxygen in the supply tank. Cucumber plants were grown in yellow cedar sawdust and pepper plants in either sawdust or perlite. Oxygen enrichment resulted in a promotion of cucumber yield in only one experiment; in two other experiments, none of the oxygen treatments, including those at sub-ambient levels, had an effect. There were no effects of oxygen enrichment on pepper yield. However, in both cucumber and pepper, fruit shelf-life was extended in oxygen-enriched treatments. In terms of system efficacy, oxygen levels in the irrigation water were measured at the dripper and found to decrease by 20–67% of initial values compared to the supply tank values, depending on the initial oxygen concentration and on the experiment. Oxygen concentrations decreased even further to virtually ambient levels when measured in the drain water or in the substrate reservoir. Cucumber plant growth was promoted under conditions which facilitated consistently high oxygen in the root zone, achieved through heavy irrigation (1 min in two) with oxygen-enriched nutrient solution of plants grown in saturated substrate (pumice). However, those extreme irrigation rates would not be practical for commercial cucumber or pepper production. Overall, this study demonstrates that oxygen enrichment of porous substrates under typical hydroponic conditions is difficult and possibly because of this, effects on yield are infrequent. However, fruit shelf-life may be improved.     

Pollen grains of heat tolerant tomato cultivars retain higher carbohydrate concentration under heat stress conditions

Exposure to high temperatures (heat stress) causes reduced yield in tomatoes (Lycopersicon esculentum), mainly by affecting male gametophyte development. Two experiments were conducted where several tomato cultivars were grown under heat stress, in growth chambers (day/night temperatures of 31/25 °C) or in greenhouses (day/night temperatures of 32/26 °C), or under control (day/night temperatures of 28/22 °C) conditions. In heat-sensitive cultivars, heat stress caused a reduction in the number of pollen grains, impaired their viability and germinability, caused reduced fruit set and markedly reduced the numbers of seeds per fruit. In the heat-tolerant cultivars, however, the number and quality of pollen grains, the number of fruits and the number of seeds per fruit were less affected by high temperatures. In all the heat-sensitive cultivars, the heat-stress conditions caused a marked reduction in starch concentration in the developing pollen grains at 3 days before anthesis, and a parallel decrease in the total soluble sugar concentration in the mature pollen, whereas in the four heat-tolerant cultivars tested, starch accumulation at 3 days before anthesis and soluble sugar concentration at anthesis were not affected by heat stress. These results indicate that the carbohydrate content of developing and mature tomato pollen grains may be an important factor in determining pollen quality, and suggest that heat-tolerant cultivars have a mechanism for maintaining the appropriate carbohydrate content under heat stress.     

Interactive effects of planting time and mulching on ‘Chandler’ strawberry (Fragaria × ananassa Duch.)

Studies were conducted in ‘Chandler’ strawberry with the aim to optimize planting time and mulching material under the semi-arid region of north Indian plains. Three planting times viz., mid-September, mid-October and mid-November and three mulch materials viz., black polyethylene (50 μm), clear polyethylene (50 μm) and paddy straw (10 cm thickness) were tried with three replications in a split plot design. Mid-September planting favoured plant growth, enhanced flowering (77.3 days), which resulted in production of significantly larger fruit (13.0 g) and higher yield (174.4 g/plant) with fruit having higher TSS (9.23%), acidity (1.22%) and ascorbic acid content (44.1 mg/100 g of pulp) with lesser incidence of albinism (9.6%) and botrytis rot (8.1%) than other plantings. Plants mulched with black polyethylene have significantly better growth, and they flowered (80.2 days) and fruited early (29.2 days), and produced larger fruit (12.6 g) and higher yield (172.4 g/plant), with slightly higher incidence of albinism (20.1%), but with lower incidence of botrytis rot (7.3%) than those mulched either with clear polyethylene or paddy straw. Planting time × mulching interaction has significantly influenced plant growth; flowering and fruiting; fruit yield and quality, and albinism and botrytis rot. Plants have best growth parameters like, plant height (11.2 cm), crown spread (24.1 cm) and leaf area (87.9 cm²), they took lesser days to flowering (73.7 days) and fruiting (31.3 days), produced larger fruit (13.7 g) and higher yield (191.3 g/plant) with fruit having higher TSS (9.41%), acidity (1.17%) and higher ascorbic acid content (46.4 mg/100 g pulp) with a slightly higher incidence of albinism (10.3%), but comparatively lower incidence of botrytis rot (5.2%) when planted during mid-September and mulched with black polyethylene than other plantings and mulched either with clear polyethylene or paddy straw. These studies indicated that strawberry could be planted in mid-September with black polyethylene mulch under semi-arid regions of India for early fruiting, and higher yield of better quality fruits.     

Root aeration improves yield and water use efficiency of tomato in heavy clay and saline soils

Water logging and salinity of the soil alter both the physical and biological environment of plant roots. In two experiments, we investigated the effects of imposed aeration on yield and the physiological response of tomato (Lycopersicon esculentum L.) variety Improved Apollo growing under protected conditions over a range of salinities (the salinity experiment), and under constant field capacity (FC) or drier soil conditions (the moisture experiment). Subsurface irrigation with aerated water (12% air in water) stimulated above-ground growth, and enhanced the reproductive performance through earliness for flowering and fruiting compared with the control. Fruit yield of tomato with aeration in the moisture experiment was increased by 21% compared with the control (4.2 kg versus 3.7 kg per plant), and the effect of aeration on fruit yield was greater in FC than in the drier treatment. Fruit yield was increased by 38% in saline soil due to aeration compared with the non-aerated control. Increasing salinity from 2 to 8.8 dS m⁻¹, and 10 dS m⁻¹ reduced fruit yield by 18% and 62%, respectively, but 4 dS m⁻¹ did not suppress yield. Aeration in both the experiments increased plant water use and water use efficiency (WUE), expressed as weight per unit of applied water. Biomass WUE was greater by 16% and 32% in the moisture and salinity experiments, respectively. The increased yield with aeration was also accompanied by an increased harvest index (HI) defined as the proportion of dry fruit biomass to total dry biomass, greater mean fruit weight, high fruit DM, and increase in leaf chlorophyll content and shoot: root ratio, and a reduced water stress index (computed from the difference between air and leaf temperature). The benefit gained from aerating irrigation water was not only observed under conditions where air-filled porosity may be low (e.g., in poorly structure sodic soils, or at field capacity in clay soils), but also in drier soils.     

Entwicklung und Regulierung eines Schaderregerkomplexes an Himbeerruten

The increasing damages on fruiting canes in raspberry plantations are caused by the disease complex ‘midge blight’, in which different fungi and the raspberry cane midge are involved. The larvae of the midges feed in the first year in primocanes and damage the periderm, so that fungal pathogens are able to penetrate into the internal cane tissues and can cause vascular lesions. Death, but failure or lateral wilt results in the second year from damages of the xylem. In a two-year-old survey the growth of canes and the development of the fungal complex and the raspberry cane midge was investigated in different plantations. The most important factors of the disease complex could be related to each other. Subsequently the influence of growth management of young canes and chemical control of the midges on the health of the canes were investigated. The delay of the emergence of the primocanes in spring reduced the occurrence of natural splits and the xylem lesions. The post-harvest applications of insecticides against the third generation of the cane midge had a similar effect, whereas the effect increased along with the delayed emergence of primocanes. This can be related to the fact that the growth management of young canes is shifting the disease complex and its main damage period so that the efficacy of chemical control measures against larvae in august will increase. The results are the base for the future development of a control strategy.