绿叶蔬菜工厂化生产关键技术研究

围绕绿叶蔬菜的清洁高效生产和均衡供应需求,借鉴日本、荷兰等国家植物工厂发展的先进经验,针对绿叶蔬菜工厂化生产的关键环节和技术突破点,以小白菜的工厂化生产为例,综述了品种选择、基质研发、肥水运筹、节能生产、绿色防控、物流加工、质量管理等关键设备与技术研究进展,探索符合中国国情的有机生态型绿叶蔬菜工厂化生产的可行性。     

拱棚叶类蔬菜复种水稻试验研究

为了充分利用宁夏富足的光、热资源,改革创新种植业耕作模式,提高农田复种指数和产出率,宁夏原种场对在水稻插秧前加种一茬全生育期为40～45 d的速生叶类蔬菜进行了试验研究。结果表明:参试的四季小白菜、菠菜、油菜、生菜、茴香、茼蒿等6种蔬菜均达到了商品菜标准,净产值在11 760.0～43 860.0元/hm2,具有很大的推广价值。     

不同浓度肥料对苗菜生长的影响

以生菜、甜菜、苦苣、红苋菜为试材,采用无土栽培方式,研究喷施不同浓度的肥料对不同苗菜生长的影响。结果表明:对苦苣、苋菜、甜菜适宜喷洒3‰浓度的肥料,对生菜类苗菜适宜喷洒5‰浓度的肥料。     

Use of detached tomato leaves to test for resistance to tomato mosaic virus

Samenvatting Een methode werd ontwikkeld om de resistentie van in de kas geteelde tomateplanten tegen tomatemozaïek virus (ToMV) te bepalen. Bladeren van een vatbare en een resistente cultivar werden afgesneden en geïnoculeerd met ToMV. Na 6, 10 en 17 dagen werden de geïnoculeerde bladeren getoetst op de aanwezigheid van virus met ELISA en door inoculatie van bladeren vanNicotiana glutinosa. Met beide toetsmethoden kon de virustoename in de vatbare cultivar al vroeg na inoculatie duidelijk worden aangetoond. In de bladeren van de resistente cultivar was een zeer kleine hoeveelheid virus pas laat na de inoculatie aantoonbaar. Met deze methode is het mogelijk om de resistentie tegen ToMV te bepalen, tevens zaad te winnen en landbouwkundige eigenschappen te evalueren, zonder de plant te infecteren.     

Genetic diversity and mixed infections of begomoviruses infecting tomato, pepper and cucurbit crops in Nicaragua

Begomoviruses were detected in Nicaraguan fields of tomato ( Lycopersicon esculentum ) and adjacently growing plants of pepper ( Capsicum annuum ), chilli pepper ( C . baccatum ), cushaw ( Cucurbita argyrosperma ) and Mexican fireplant ( Euphorbia heterophylla ) using polymerase chain reaction (PCR) and universal begomovirus primers. All tomato and Mexican fireplant plants showing symptoms were infected with begomoviruses, while only 30–46% of the pepper, chilli pepper and cushaw plants showing symptoms tested virus-positive. No begomoviruses were found in potato. The virus species were provisionally identified by sequencing 533 bp of the viral coat protein gene ( AV1 ). Tomato severe leaf curl virus (ToSLCV), Tomato leaf curl Sinaloa virus (ToLCSinV) and Pepper golden mosaic virus (PepGMV) were found to infect both tomato and pepper. A new provisional species designated Tomato leaf curl Las Playitas virus (ToLCLPV) was detected in a tomato plant. Squash yellow mottle virus (SYMoV) and PepGMV were found in cucurbits, the latter for the first time in this host. Euphorbia mosaic virus (EuMV) was detected in Mexican fireplant. Sequencing of a larger number of PCR-amplified clones from selected plants revealed intraspecific viral sequence variability, and also multiple begomovirus infections which could represent up to three species in a single tomato or cushaw plant. Phylogenetic grouping of virus sequences did not correlate with the host of origin.     

Effects of acid extracts of tomato (Lycopersicon esculentum Mill.) and carrot (Daucus carota L.)wastes from the food industry on the growth of some crops and weeds

The effects of acid extracts of tomato ( Lycopersicon esculentum Mill.) and carrot ( Daucus carota L.) juice wastes from the food industry on the growth of five species of crops and four weeds were examined. The acid extract of the tomato juice waste promoted the shoot and root growth of tomato, Chinese cabbage, corn, and radish, but not the growth of oat seedlings. The extract did not promote the shoot growth of weeds tested, and it inhibited the root growth of the weeds that included barnyardgrass ( Echinochloa oryzicola Ohwi), southern crabgrass ( Digitaria ciliaris Koel.) and Japanese barnyard millet ( Echinochloa utilis Ohwi). The carrot juice waste was also examined as another waste from the food industry. The effect of the acid extract of carrot juice waste showed significant promoting effects on the root growth of Chinese cabbage; however, the effects on other plants were lower than that of tomato juice waste. It also did not inhibit the growth of weeds. These results suggested that the acid extract from tomato juice waste is useful as plant-growth substances because they have a promoting effect on the shoot and root growth of crops, and an inhibitory effect on the root growth of some weeds.     

Threshold values for chemical control of powdery mildew (Erysiphe cruciferarum) on Brussels sprouts

To establish control thresholds for chemical control of powdery mildew (Erysiphe cruciferarum) on Brussels sprouts, mildew intensity on leaves and buds was observed on the cultivars Lunet, Tardis and Asgard during three years in unsprayed plots. Mildew infection on the leaves was observed from late August onwards, increasing to moderate or high levels. In one year light infestation of the buds was observed, but no reduction in quality occurred. These preliminary results indicate, that from late August onwards the following levels of leaf injury by powdery mildew can be tolerated: T=5+0.42^*(Julian date — 235), in which T is the tolerable leaf injury in percentage leaf area covered. When sampling the crop to assess powdery mildew infection, care must be taken that leaves are sampled from all stem positions, as top leaves tend to be much less infected.     

Selection forMeloidogyne incognita virulence against resistance genes from tomato and pepper and specificity of the virulence/resistance determinants

Experiments were designed to analyze the relationships between the root-knot nematodeMeloidogyne incognita and resistant tomato and pepper genotypes. From a natural avirulent isolate, near-isogenic nematode lineages were selected with virulence either against the tomatoMi resistance gene or the pepperMe3 resistance gene. Despite the drastic selection pressure used, nematodes appeared unable to overcome the pepperMe1 gene, therefore suggesting some differences in the resistance conferred byMe1 andMe3 in this species. Nematodes virulent onMi-resistant tomatoes were not able to reproduce onMe1-resistant nor onMe3-resistant peppers, and nematodes virulent onMe3-resistant peppers were not able to reproduce onMi-resistant tomatoes nor onMe1-resistant peppers. These results clearly demonstrate the specificity ofM. incognita virulence against resistance genes from both tomato and pepper, and indirectly suggest that gene-for-gene relationships could occur between these two solanaceous crops and the nematode.     

A new aggressive strain of Verticillium albo-atrum in Verticillium resistant cultivars of tomato in the Netherlands

In 1991 serious losses caused byVerticillium wilt were found on two holdings in the Westland glasshouse district in the Netherlands in which theVerticillium resistant tomato cultivars Calypso and Criterium were grown in soilless systems. Isolates from diseased plants were identified asVerticillium albo-atrum.In inoculation experimentsVerticillium resistant tomato cultivars were seriously affected by the new isolates but not by a control isolate. Moneydor, a susceptible cultivar without the Ve gene, was the most seriously diseased by all isolates. The isolates from theVerticillium resistant tomato cultivars were less virulent on the susceptible cultivar than the control isolate.     

Seedborne fungi detected on stored solanaceous berry seeds and their biological activities

We isolated 629 fungi from 1296 berry seeds of solanaceous plants, including tomato (Lycopersicon esculentum), eggplant (Solanum melongena), bell pepper (Capsicum annuum), and red pepper (Capsicum annuum var. annuum) preserved for long and short terms. The isolates were classified into 22 genera excluding unidentified fungi, and the fungal floras were divided into two types: the tomato–eggplant and pepper groups. The results of cluster analysis with unweighted pair-group method with arithmetic average also supported these groups. Most tomato seeds infested with Geotrichum candidum germinated and grew the same as uninfested seeds. Cladosporium sphaerospermum and Arthrinium sp. isolated from eggplant seeds strongly suppressed germination, and Penicillium variabile suppressed seminal root elongation on eggplant. Alternaria alternata, Botrytis cinerea, and Myrothecium verrucaria detected from red pepper or bell pepper seeds were pathogenic to the fruits and the seedlings after artificial inoculation.