Survival in soil of bacteria causing common and halo blights of French bean in Victoria

1980 ◽  
Vol 20 (102) ◽  
pp. 102 ◽  
Author(s):  
DLS Wimalajeewa ◽  
RJ Nancarrow

Survival of Pseudomonas phaseolicola and Xanthomonas phaseoli in soil between successive bean crops was studied in a field situation at Bairnsdale. P. phaseolicola and X. phaseoli survived on nylon netting for maximum periods of 6 and 3 weeks, respectively, on the soil surface, and for 6 and 2 weeks when buried. On infected leaf, stem and pod tissue P. phaseolicola survived for 20 weeks on the soil surface and for 11 weeks when buried; X. phaseoli survived up to 11 weeks on the soil surface and for 3 weeks when buried. In heavily infected bean plots neither pathogen was carried over from one growing season to the next. It is concluded that infected bean debris in the soil from the previous growing season is not a source of common and halo blight infection in East Gippsland.

2021 ◽  
Vol 25 (7) ◽  
pp. 8-12
Author(s):  
Z.G. Lamerdonov ◽  
T.Yu. Khashirova ◽  
S.A. Zhaboev ◽  
L.Zh. Nastueva ◽  
A.А. Shogenov ◽  
...  

The results of experimental studies of the local subsurface irrigation method in comparison with drip irrigation carried out in the laboratory, which showed water savings due to a decrease in evaporation from the soil surface by 10–15 percent are presented. The method of irrigation in closed greenhouse farms using water with a high salt content is described. The paper proposes new patented schematic solutions for protecting plants from frost and pests, describes a multifunctional engineering and reclamation system capable of performing various operations depending on the emerging problems during the growing season.


Genetika ◽  
2013 ◽  
Vol 45 (1) ◽  
pp. 261-272 ◽  
Author(s):  
Branka Kresovic ◽  
Vesna Dragicevic ◽  
Bosko Gajic ◽  
Angelina Tapanarova ◽  
Borivoj Pejic

The aim of the present study was to observe the response of maize hybrids under rainfed and irrigation conditions of the soil in order to establish the dependence of yielding potential on the water amounts reaching the soil surface during the growing season. The four-replicate trail was set up according to the randomised complete-block design on chernozem. Pre-watering soil moisture was approximately 70% of field water capacity, and soil moisture was established thermogravimetrically. During the five-year studies, the following differences in yields could be as follows: 12.68 t ha-1 (ZP 341); 12.76 t ha-1 (ZP 434); 13.17 t ha-1 (ZP 578); 14.03 t ha-1 (ZP 684) and 13.75 t ha-1 (ZP 704) under conditions of 440 mm, 440 mm, 424 mm, 457 mm and 466 mm of water, respectively. The hybrid ZP 341, i.e. ZP 578 expressed the highest, i.e. the lowest tolerance in dry relative seasons, respectively. The reduction of the water amount for every 10 mm decreased the yield by 119.4 kg ha-1 (ZP 341), 156.7 kg ha-1 (ZP 434), 172.3 kg ha-1 (ZP 578), 148.9 kg ha-1 (ZP 684) and 151.1 kg ha-1 (ZP 704).


1978 ◽  
Vol 18 (91) ◽  
pp. 318
Author(s):  
DLS Wimalajeewa ◽  
RJ Nancarrow

The incidence of common blight, halo blight and brown spot on French beans was surveyed in the Bairnsdale-Lindenow and Orbost areas in East Gippsland during the 1975-76 and 1976-77 growing seasons. Common blight and halo blight were severe only during late January to March, and occurred largely on mature crops. Common blight was the more severe disease in the Orbost area whereas halo blight was more severe in the Bairnsdale-Lindenow area. Brown spot occurred throughout the season on crops of all ages in both areas but was more severe in the Bairnsdale-Lindenow area. The relationship of weather to the incidence of bacterial blights in the two areas is discussed. It is inferred that losses due to common blight and halo blight could be considerably minimized by timing the planting of crops to harvest them by mid-February.


1991 ◽  
Vol 31 (3) ◽  
pp. 357 ◽  
Author(s):  
RJ Jarvis ◽  
MDA Bolland

Five field experiments with lupins (Lupinus angustifolius) measured the effectiveness, for production, of 4 superphosphate placements either: (i) drilled with the seed to a depth of 4 or 5 cm; (ii) applied to the soil surface (topdressed) before sowing; or (iii) banded 2.5-5 cm and 7.5-8 cm below the seed while sowing. Levels of applied phosphate (P) from 0 to 36 kg P/ha were tested. In all experiments lupin grain yield responded to the highest level of superphosphate applied. At this P level, the average grain yield from all trials was 1.16 t/ha for the deepest banded treatment. This was 0.38 t/ha (49%) better than P drilled with the seed, and 0.62 t/ha (115%) better than P topdressed. Relative to superphosphate drilled with the seed and regardless of the lupin cultivar or the phosphate status of the soil, the effectiveness of superphosphate was increased by 10-90% by banding below the seed, and decreased by 30-60% by topdressing. Increasing the levels of superphosphate drilled with the seed generally reduced the density of seedlings and reduced early vegetative growth, probably due to salt or P toxicity. However, during the growing season, the plants treated with high levels of superphosphate recovered, so that eventually yields of dried tops and grain responded to increasing superphosphate drilled with the seed. In each experiment there was a common relationship between yield and P content in lupin tissue, regardless of how the superphosphate was applied, suggesting that lupins responded solely to P, and other factors did not alter yield. We recommend that farmers band superphosphate 5-8 cm below the seed while sowing, rather than continue the present practices of either drilling the fertiliser with the seed, or topdressing it before sowing.


1999 ◽  
Vol 13 (2) ◽  
pp. 341-346 ◽  
Author(s):  
Thomas C. Mueller ◽  
David R. Shaw ◽  
William W. Witt

The dissipation of four commonly used soil-applied herbicides was examined in a standardized field experiment in three southern states (Kentucky, Mississippi, and Tennessee). Averaged over the three soils and 2 yr, the relative order of increasing half-life defined as time for 50% disappearance in days (DT50) was acetochlor (6.3 d) = alachlor (6.3 d) = SAN 582 (7.3 d) < metolachlor (13.7 d). Metolachlor was the most persistent in the soil surface, and this could potentially translate into greater duration of weed control into the growing season. All examined herbicides had a DT50that averaged less than 14 d in all states in both years, so full-season weed control of susceptible species would not be expected. Rapid herbicide degradation was encouraged in these field sites by adequate to excessive soil moisture and warm temperatures throughout the sampling interval. The soils also were light textured, and the lower adsorption of the herbicide allowed for degradation ease and perhaps leaching below the sampling depth.


1975 ◽  
Vol 53 (24) ◽  
pp. 3022-3031 ◽  
Author(s):  
A. G. Thomas ◽  
H. M. Dale

In the crowded parts of patches of Hieracium floribundum Wimm. and Grab., which were established for at least a decade in an ungrazed pasture, 7–10% of the population (3700 individuals/m2) flowered. Of the plants that flowered, 94% were alive a year later, but only 5% of these flowered. Abortion of flower heads was common; one half of all those which were initiated in early June had aborted by flowering time in early July. Freshly dispersed seed had a viability of 57%, which was reduced to 17% a year later, after its storage close to the soil surface. Less than 6% of the viable seed was innately dormant. Dry, laboratory-stored seed retained its viability for the year but was slower to germinate than soil-stored seed. In field conditions, germination was temperature inhibited during most of the growing season. Maximum daytime microsite temperatures of less than 32 °C, which is necessary for germination, were found to occur only in early spring and late fall. Successful seedling establishment accounts for 1% of the individuals in a crowded population. Based on the maximum sexual reproduction from plants in crowded populations, a seed has a probability of 1 in 20 000 of becoming an established seedling. A model of population dynamics in a high-density patch traces the fate of seedling establishment, surviving adults, and stolon-derived rosettes for a single year.


2006 ◽  
Vol 46 (9) ◽  
pp. 1207 ◽  
Author(s):  
M. T. Treeby ◽  
D. M. Wheatley

The growth and nitrogen (N) percentage of the annual components and the N percentage of the perennial components of unfertilised and fertilised (100 kg N/ha.season) irrigated grapevines (Vitis vinifera cv. Sultana syn. Thompson Seedless) were compared over 2 consecutive seasons. Leaf, stem and fruit samples were measured for dry matter yield and N content at about fortnightly intervals during the growing season, and samples of 1–2-year-old wood, trunk, cane and root were sampled for N content at about fortnightly intervals during the growing season and 4-week intervals during dormancy. Total vine biomass was assessed on unfertilised vines following fruit harvest in the second season. Total vine biomass at this time was about 13.1 kg dry matter/vine, 43% of which was below the soil surface. Dry matter and fruit yield of vines did not respond to N application until the second season with an increase in annual biomass and fruit yield of 75 and 140%, respectively. The N contents of all vine organs were related to vine phenology, with N percentage decreasing in all annual parts during the season. The N percentage in perennial parts was lowest near flowering and fluctuated from then until harvest depending on demand by annual parts, principally leaves and fruit, and supply.


Author(s):  
A.S. Zhangabaeva ◽  
A.K. Saitova ◽  
L.A. Gafurova ◽  
R.F. Mavlyanova

Топинамбур ценная культура, используемая в различных отраслях. Цель исследований: оценка адаптивности сортов топинамбура Файз-Барака и Мужиза к условиям жаркого сухого климата и засоленных почв, а также разработка важнейших элементов технологии для получения урожая в экстремальных условиях. Климатические условия характеризуются резко континентальным климатом, очень жарким летом и холодной зимой. В Кегейлинском районе, где проводились испытания, незначительное количество осадков в весенний период (510 мм), их отсутствие в летние месяцы и постоянный ветер способствуют низкой относительной влажности воздуха (1128) и засушливости. В летний период температура днем повышается до 4043 C, что вызывает стресс у всех произрастающих культур. Почвы участка, где проводили исследования-лугово-аллювиальные, легкосуглинистые, слабозасоленные, тип засоления-хлоридно-сульфатный. В пахотном горизонте содержание гумуса составляет 0,871,03, валового азота 0,100,12, фосфора 0,230,28, калия 2,52,7 мг/кг, а обменного калия 197305 мг/кг почвы. В период вегетации соли постепенно поднимаются в корнеобитаемый слой и на поверхность почвы, что отрицательно влияет на рост и развитие культур. Агротехнические мероприятия включали промывку почвы от солей в зимний период водой (35004000 м3/га), вспашку, боронование, нарезку борозд, две культивации в период вегетации, внесение минеральных удобрений общей нормой N100P150K100 (д.в.), 34 полива с нормой 600650 м3/га. Факторы и варианты опыта: два сорта топинамбура при четырех сроках посадки клубней, трех схемах посадки, трех фракциях массы клубня и трех вариантах глубины посадки. Каждый опыт закладывали в четырехкратной повторности рендомизированным способом. Площадь делянки каждого варианта опыта составляла по 55 м2. Использовали стандартные методики. При оптимальном сроке посадки клубней 5 апреля, клубнями массой 4060 г на глубину 910 см по схеме 7040 см обеспечивается наибольшая урожайность у сорта Файз-Барака (2,79 кг/м2) и Мужиза (3,02 кг/м2).Jerusalem artichoke is a valuable crop used in various branches of industry. The goal of the research is to assess the adaptability of Jerusalem artichoke Fayz-Baraka and Muzhiz cultivars to the conditions of hot dry climate and saline soils, as well as to develop the most important elements of the technology for obtaining a yield in extreme conditions. Climate conditions are characterized by a sharply continental climate, very hot summers and cold winters. In The Kegeyli region where the tests were conducted, the low amount of precipitation in the spring (510 mm), their absence in the summer months and constant wind contribute to low relative humidity (1128) and dryness. In summer, the daytime temperature rises to 4043 C, which causes stress for all growing crops. The soils of the area where the research was carried out are meadow-alluvial, light-loamy, slightly saline, and the type of salinity is chloride-sulfate. In the arable horizon, the humus content is 0.871.03, gross nitrogen 0.100.12, phosphorus 0.230.28, potassium 2.52.7 mg/kg, and exchange potassium 197305 mg/kg of soil. During the growing season, the salt gradually rises in the root layer and on the soil surface, which negatively affects the growth and development of crops. Agrotechnical measures included washing the soil from salts in winter with water (35004000 m3/ha), plowing, harrowing, cutting furrows, two cultivations during the growing season, applying mineral fertilizers with a General norm of N100P150K100 (act. subst.), 34 watering with a norm of 600650 m3/ha. Factors and experience options: two varieties of Jerusalem artichoke with four terms of planting tubers, three planting schemes, three fractions of the mass of the tuber and three options for planting depth. Each experiment was laid out in a four-fold repetition in a rendomized way. The plot area of each variant of the experiment was 55 m2. We used standard methods. The optimal term for tubers planting on April 5, planting tubers weighing 4060 g to a depth of 910 cm according to the 70x40 cm scheme provide the highest yields for the variety Fayz Baraka (2.79 kg/m2) and Mujiza (3.02 kg/m2).


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