Search Results
Abstract
The response of 11 cultivars of potato (Solanum tuberosum L.) to preemergence, preemergence + postemergence, and early postemergence applications of metribuzin [4-amino-6-ferf-butyl-3-(methylthio)-as-triazin-5 (4H)-one] was studied over a 5-year period (1973–1977). Postemergence sprays applied at temperatures over 21°C increased injury and decreased yields. ‘Belleisle’, ‘Early Rose’, ‘Kennebec’, ‘Netted Gem’, ‘Red La Soda’, ‘Red Pontiac’ and ‘White Rose’ were more sensitive to metribuzin at these temperatures than ‘Epicure’, ‘Norgold Russet’, ‘Norland’, and ‘Warba’. Cultivars responded to the amount of sunshine before, during, and after spraying with metribuzin. When the weather was very cloudy on the 3 days before and on the day of spraying and then sunny for the next 3 days, metribuzin injured ‘Belleisle’, ‘Netted Gem’, ‘Red Pontiac’, and ‘Warba’. ‘Belleisle’, ‘Epicure’, ‘Norland’, ‘Red La Soda’, ‘Red Pontiac’ and ‘White Rose’ when grown under stress caused by lack of water, were more sensitive to the herbicide than the other cultivars under test. ‘Epicure’, ‘Netted Gem’, ‘Norgold Russet’, ‘Norland’ and ‘Warba’ grown in wet soil were more sensitive to preemergence applications than other cultivars. Cultivars differed in their tolerance to metribuzin and were classified as follows: ‘Norgold Russet’ and ‘Epicure’, most tolerant; ‘Kennebec’, ‘Early Rose’, ‘Netted Gem’, ‘Red La Soda’ and ‘Norland’, intermediate; and ‘Belleisle’, ‘Red Pontiac’, ‘Warba’ and ‘White Rose’, most susceptible.
Abstract
The compatibility of 5 preemergence herbicides and 3 insecticides applied in silt loam was assessed in 4 brassica crops by comparing their effects on germination, plant stand, and yield. Several combinations were deleterious. The herbicides CDEC and DCPA in combination with the insecticide thionazin reduced plant stand in cabbage and cauliflower. Herbicide C-7019 in combination with the insecticide fensulfothion was incompatible for cabbage and broccoli. Cabbage germination was reduced; while with broccoli both the germination and crop yield were affected. C-7019 alone reduced the germination of cauliflower and in combination with fensulfothion the damage was increased. This herbicide was phytotoxic to rutabaga. When nitrofen was combined with the insecticides, plant stands of cauliflower and rutabaga were affected. Nitrofen and thionazin together reduced the plant stand of cabbage. Propachlor at 4 lb./acre was compatible with any of the three insecticides for the four crops. However, the plant stand and yields of all four crops were reduced in plots treated with propachlor at 6 lb./acre in combination with thionazin. Propachlor with the insecticide carbofuran injured only broccoli. The herbicides did not affect the efficacy of the insecticides.
Abstract
Over a 6-year period (1969-1974) the efficacy of 25 herbicides and 3 insecticides and their interactions in combination were investigated when applied to field seeded rutabaga (Brassica napobrassica). Of 215 herbicide insecticide combinations tested only 29 resulted in phytotoxic interactions as measured by seedling emergence, plant height and marketable yield. Six combinations involved all the insecticides: thionazin, fensulfothion and carbofuran; 1 with carbofuran and thionazin, 1 thionazin and fensulfothion, 5 thionazin alone, and 2 fensul fothion alone. Only 6 herbicides were involved: alachlor, aziprotryn, pronamide, napropamide, prynachlor and chlorpropham; the last when combined with propachlor. Although fewer emergent seedlings were recorded with all insecticides in 1969 to 1971 only thionazin caused a significant reduction. Carbofuran and thionazin affected rutabaga growth detrimentally in the years 1969 to 1971, but in the following years carbofuran had no effect. Plant growth was not affected during any year by fensulfothion. In all years the insecticides resulted in significant increases in marketable yields of rutabaga, carbofuran was slightly better for control for cabbage maggot, Hylemya brassicae (Bouché) than either fensulfothion or thionazin. None of the herbicides showed any insecticidal properties, nor did they affect the efficacy of the insecticides.
Abstract
Over a 6-year period (1969-1974) the efficacy of 3 insecticides and 24 herbicides and their interactions in combination were investigated when applied to field-seeded broccoli (Brassica oleracea L. Italica group), cabbage (Capitata group) and cauliflower (Botrytis group). Of these, broccoli was the most susceptible to injury. Of 212 herbicide-insecticide combinations, 26 caused phytotoxic symptoms in broccoli, 20 in cabbage and 8 in cauliflower. The insecticides, thionazin, fensulfothion and carbofuran, were each involved in 1 or more phytotoxic combinations in each of the 3 crops. Ten herbicides were involved in phytotoxic reactions: alachlor, aziprotryn, benefin, CDEC, chlorpropham, cycloate, prometryne, propachlor, prynachlor and PP493. Root maggot damage was reduced markedly by the insecticides. Carbofuran allowed less damage than either fensulfothion or thionazin. None of the herbicides showed any insecticidal properties, and some decreased the effectiveness of the insecticides.
Abstract
Virus-free (VF) plants of 6 cultivars of red raspberry (Rubus idaeus L.) were graft-inoculated with raspberry bushy dwarf (RBDV)-infected scions. Plants grown from root cuttings of the inoculated plants were established in a replicated field trial and their performance was compared with noninoculated plants for 4 years. ‘Haida’ and ‘Willamette’ did not become infected with the virus either by graft inoculation or by pollen transmission. The other cultivars, ‘Creston’, ‘Canby’, ‘Lloyd George’, and ‘Meeker’, were infected by graft inoculation. Moreover, after 4 years, all of the original VF plants of these cultivars were infected. Differences in virus effects between the original VF and RBDV-infected clones were greatest for ‘Meeker’ and least for ‘Creston’. Black raspberry necrosis virus (BRNV) was not associated with RBDV infection in Meeker although the cultivar is susceptible to the aphid vector of BRNV.
Abstract
As part of the study on the effect of viruses on the growth and fruiting of red raspberry cultivars, drupelet set of fruit was studied. Clones of four cvs., Fairview, New-burgh, Sumner and Willamette were infected with black raspberry necrosis (BRNV), raspberry mosaic (RMV), tomato ringspot (TomRSV) and raspberry vein chlorosis (RVCV). Significant reduction in drupelet set, expressed as crumbliness, occurred only in the TomRSV-infected clones of ‘Sumner’ and ‘Fairview’, and for the latter, it occurred only on those plants which showed relatively severe symptoms of decline.
Abstract
Raspberry bushy dwarf virus (RBDV) was found in 25 of 75 cultivars maintained in the British Columbia red raspberry (Rubus idaeus L.) breeding program. Crumbly-appearing fruit and leaf abnormalities were associated with infection in some of the cultivars. No RBDV was found in commercial fields of the Willamette cultivar. Comparisons of RBDV-infected and virus-free plants of BC 64-6-68, a selection from the breeding program, showed that the virus reduced yield and fruit size, and increased drupelet abortion resulting in crumbly fruit. RBDV infection did not affect vegetative growth. Field spread of the virus in BC 64-6-68 was through pollen.
Abstract
A trial of six raspberry (Rubus ideaus L.) cultivars was established to study the effects of primocane removal, using dinoseb, on yield and its components. In 1982 through 1984, sprays were applied using both single and multiple follow-up treatments with and without shielding the primocanes in the immediate stool area. The effects of cultivars and treatments on yield components were studied by two-dimensional partitioning of the variation in marketable yield. When primocanes were removed, the cultivars had fewer canes, larger fruit, and increased marketable yield. Cultivars differed in their requirements for treatment because some cultivars produced canes more readily than others. Higher-yielding cultivars generally had fewer canes and greater length of laterals. Chemical name used: 2-(1-methylpropyl)-4,6-dinitrophenoI (dinoseb).
Abstract
Survival and vigor, after −1°C storage, of Totem strawberry (Fragaria × ananassa Duch.) plants dug at 8 different dates, from November 15, 1973 to April 1, 1974, was affected adversely only when dug April 1. Predigging treatment with Methyl 1-(butylcarbamoyl)-2-benzimidazolecarbamate(benomyl) did not affect survival or vigor from any of the dates. In 1975, digging date (March 1 vs April 1) did not affect the survival of plants of 4 cultivars or 6 selections. However, plants of ‘Totem’ and ‘Northwest’ and 2 selections dug April 1 showed reduced vigor compared to those dug March 1.