YIELD AND YIELD ATTRIBUTES OF RAPESEED AS INFLUENCED BY DATE OF PLANTING

ABSTRACT (Ghosh and Chatterjee, 1988) . The average yield of mustard in this country is 739 kg/ha whereas the world average yield of mustard is 1575 kg/h

Plant spacing - a non polluting tool for aphid (Hemiptera: Aphididae) management in canola, Brassica napus

Current study was initiated to generate the information on the effect of row-to-row distance of brassica crop, Brassica napus L., on aphids population. Three line spacing (20, 30 and 40 cm) with a constant nine cm plant to plant distance were evaluated on aphids infestation and its impact on seed yield. The collected and edited data on fixed parameters indicated that an inverse relation was found between increased line spacing and aphids population. It was evident that the mustard aphid, Lipaphis erysimi (Kaltenbach), population increased significantly as the inter row spacing decreased. Distance of 30 cm was quite respondent towards holding aphids number and grain yield, where optimum number of aphids (103.00 per plant) was recorded with maximum yield (980.00 Kg/Hectare). Maximum mean aphids number (163.5) was observed on the plants spaced at 20 cm apart rows with minimum seed yield (683.20 Kg). Minimum mean number of aphids (63.3) was recorded from the lines grown at the distance of 40 cm from each other with 783.20 Kg yield. The information accruing from this study showed that in areas where aphids problem is endemic, narrow rows spacing would tend to increase aphids population. Therefore, the row-to-row spacing not less than 30 cm with nine cm plant-to-plant distance is recommended in oleiferous brassica especially canola crop, as a component of integrated pest management tool to culturally control of aphids

Dissection of Year Related Climatic Variables and Their Effect on Winter Rapeseed (Brassica Napus L.) Development and Yield

Winter oilseed rape (WOSR) production is dependent on weather conditions, but is also characterized by low nitrogen (N) use efficiency. The objectives of this study were to: (i) evaluate sources of variability for the seed yield and oil content of four rapeseed cultivars under the influence of three sowing dates (SD trial) and five nitrogen dosages (N trial) during four growing seasons; (ii) understand year-related interactions and the effect of climatic variables in different growth stages; and (iii) assess the presence of interactions cultivar by year (C x Y) and treatment by year (T x Y). Six climatic factors were observed, during germination, overwintering, budding, flowering and ripening. The mixed effect split-plot analysis of variance was used, as well as factorial regression models. The C x Y interaction was the most important for the oil content in both trials. The precipitation at budding stage (75.8%), relative air humidity at overwintering (63.3%) and flowering stage (53.0%) accounted for the highest proportion of T x Y interaction for the seed yield, as well as precipitation at flowering (92.0%) and ripening (85.0%) for the oil content. Water availability was the main determinant of the seed yield and/or oil content accompanied with cooler temperatures during the seed development. The study successfully dissected the effect of year-related climatic variables on the agronomical traits in winter rapeseed. Based on this, appropriate agronomic practices can be applied at specific growing stages to ensure a high seed and oil yield

The influence of agroecological and agrotechnological factors on the generative development of oilseed radish (Raphanus sativus var. oleifera Metzg.)

Received: April 1st, 2022 ; Accepted: May 28th, 2022 ; Published: June 22nd, 2022 ; Correspondence: [email protected]; [email protected] the eight-year research period, we determined the peculiarities and regularities of morphological (length and diameter) and anatomical (stem thickness) features of oilseed radish pods considering their location within the generative part of plants for different types of spatial structure of the inflorescence generated in agrocenosises of different densities. We carried out the analysis and statistical grouping of morphological features of oil radish pod in the full range of possible technological options of pre-sowing construction of its agrocenosises, as well as within the selected three zones (tiers) of inflorescence by the nature of variation and variability of morphoparameters pod, namely, lower, middle and upper. We described in detail the stages of pod formation (microstages ВВСН 69-87) considering features of its linear and radial growth, peculiarities of formation of general internal anatomical structure with analysis of mathematical and statistical regularities of changes in these parameters in accordance as per order of its placement within an inflorescence (separately main axis and system of lateral branches). We determined the optimum technological intervals for the construction of oilseed radish agrocenosises, which ensure the combination of appropriate levels of morphometry formation of its fruit elements with the predicted level of reproductive effort and seed productivity. We made a general assessment of the peculiarities of formation of pod technological effectiveness in terms of ease of threshing and possible losses of seeds depending on the complex of factors under study

Effect of nitrogen levels on growth, yield and oil quality of Indian mustard grown under different plant densities

The study investigated agronomical and qualitative features of Indian mustard in a semi-arid region from Iran. Field trials were designed in split plot arrangement based on a Randomized Complete Block Design with three replicates at the Agricultural Faculty of Takestan, Iran. In the study, plant height (cm), the number of seeds in the siliqua (seed/siliqua), the number of siliquae in the plant (siliqua/plant), seed yield (kg/ha), biological yield (kg/ha), thousand-seed weight (g), harvest index (%), oil content (%) and oil yield (kg/ha) were determined. The all growth and yield parameters of mustard plant were significantly affected by nitrogen fertilization. All the parameters, except for harvest index (HI), were drastically affected by used densities. The highest seed yield and oil yield (2961 and 1159 kg/ha, respectively) were obtained for the crop utilized with 200 kg N/ha in plots with 80 plants/m2. The maximum oil content (43.97%) was recorded in the lowest plant density (80 plants/m2) and nitrogen application level of 50 kg/ha. Results suggest that in semi-arid region of Takestan, researchers must direct their selection treatments to increase oil quality of Indian mustard

Growing Degree Day and Seed Yield Relationships in Mustard (Brassica juncea L.) Under Different Sowing Seasons and Locations of Turkey

Mustard is grown in mild winter regions as late fall and in hard winter regions as late spring crop. Mustard has high degree of adaptability under wide range of climatic conditions in Turkey. Temperature is an important weather parameter affecting the growth and development of the mustard. The sum growing degree day (GDD) for a growing season is related to plant development which is depends on the accumulation of heat. The aim of this study was to determine the adaptation of mustard, under sowing seasons (spring and fall sowing) and locations in terms of crop growth (emergence, 50% flowering, physiological maturity, and sum growing degree days) and seed yield of mustard. Two-year field experiments in a split-plot design with four replications were carried out during 2013-14 and 2014-15 growing seasons at eight different ecological locations. These locations included Ankara, Aydin, Erzurum, Eskisehir, Isparta, Tekirdag, Tokat and Sanliurfa provinces of Turkey-as classified by Koppen-Geiger ecological conditions. The Brassica juncea L. (mustard seeds) were collected from wild conditions in the Konya province of Turkey. The results showed that, sowing seasons and locations significantly affected seed yield and GDD. The maximum seed yield of 3754.9 kg ha(-1) was obtained from Tokat (warm humid) during fall sowing with total accumulated GDD of 1512.1 degrees C for mustard. Sum growing degree-days accumulated in different sowing seasons and locations occurred between 1132.0 degrees C and 2285.1 degrees C depending on the related ecological conditions. Fall season crop in Aydin location had the maximum growing degree days. Overall, fall season accumulated more growing degree days due to longer period of sunshine in comparison to spring season with less sunshine days resulting in longer vegetation period

The epidemiology and control of Leptosphaeria maculans cause of Crucifer Blackleg, in KwaZulu-Natal.

Thesis (Ph.D.)-University of Natal, Pietermaritzburg, 1996.The perfect stage of Leptosphaeria maculans is reported for the first time in South Africa. Viable pseudothecia and pycnidia were found on dead, weathered tissue, sometimes in close association, whereas only pycnidia were found on live tissue. Some seedlots of imported cabbage seed were found to be internally infected with L. maculans at low levels and Alternaria brassicicola at higher levels. Fungicides iprodione (dicarboximide), triforine and propiconazole (sterol-biosynthesis inhibitor) eliminated both pathogens from infected seed. In a field trial of eight cabbage and two cauliflower cultivars, incidence of stem infection by L. maculans ranged from 16-80%. Two seedlots of the cabbage cultivar Gloria Osena differed in blackleg stem susceptibility. No correlation was found between stem lesion incidence and foliar infection counts of each cultivar, or stem lesion incidence and each cultivar's average days-to-harvest. In a second trial, incidence of stem infection ranged from 50% (Rotan) to 95% (Dynasty) in cabbage, and 64.2 to 96.6% in cauliflower cultivars. All Brussels sprouts and broccoli cultivars tested were highly susceptible. The cultivars of turnip and tyfon tested were observed to be immune to blackleg, whereas the swedes, Japanese radish, chou moullier and red cabbage cultivars tested were highly susceptible. No correlation was found between stem length and incidence of stem infection. Different seedlots within several cabbage and cauliflower cultivars differed in their blackleg susceptibility. A third cultivar trial with 10 replicates of four seedlots of one cabbage cultivar confirmed that different seedlots of a single cultivar may vary significantly in their susceptibility to blackleg. Benomyl was applied to cabbage at the seedling stage only, or at the seedling stage followed by field applications every 14 d. Relative to an untreated control, multiple applications of benomyl resulted in a 33% reduction in stem infection, a ten-fold reduction in plants killed and a 50% reduction in the proportion of non-harvestable heads, relative to an untreated control. Seedling treatment resulted in a lower infection level, a lower mortality rate and a greater mean head mass than those of the untreated control. However, none of these differences were statistically significant. In a debris degradation trial, more than 90% of buried debris (cabbage stems infected by L. maculans) had decomposed after 2.5 yr, whereas 80% of surface debris had decomposed over the same period. The susceptibilities of seedbed transplants (SBT) and container-grown seedlings (CGS) were compared using different forms of L. maculans inoculum. "Dunk" inoculation of SBT into a pycnidiosporial suspension resulted in a stem infection level of 50% greater than an uninocu1ated control. Contamination of seedbeds resulted in an infection level of 46%. "Dunk" inoculation of CGS resulted in infection level of 22%. When CGS were grown in contaminated trays an infection level of 33.4% resulted. Interplot interference ill the form of inoculum dispersal over a 1 m border was low (1.8 and 2.7% for SBT and CGS, respectively) . In a further trial examining the relationship of inoculum level and blackleg, a strong interaction was found between inoculation technique and inoculum level. Inoculation of field plots with infected debris was a more efficient technique than dipping seedlings into a pycnidiospore suspension prior to transplanting. Twenty nine blackleg epidemics were surveyed over 11 yr. Seedbed transplants (SBT) had been used in 83% of cases. Two cases (7%) had involved direct drilled seedlings (DDS). However, excess seedlings had been transplanted, making DDS epidemiologically equivalent to SBT. Three cases (10%) had involved container-grown seedlings (CGS) grown on mono cropped cabbage lands. Disease occurred in two patterns: in crops grown from SBT and DDS, blackleg occurred down the lines. In all CGS cases, disease occurrence was randomly patterned. In all cases, diseased debris was found in seedbeds and production fields. Disease spread in the field was limited to the two plants on either side of the initially infected plant, 1.3 m or less, suggesting that infection had resulted from splash dispersed pycnidiospores. The disease cycle was mono- or oligo cyclic but not polycyclic. Over a period of 6 yr, cabbage fields of 26 farms were each examined once for cruciferous weeds infected with L. maculans. No viable blackleg lesions were discovered on cruciferous weeds, suggesting that weeds play no role in the local crucifer blackleg pathosystem. A theory is proposed that windows of disease susceptibility open and shut during the different phenological stages of a crucifer's life, and that the susceptibility of different plant organs vary with the phenological state of the plant. It is also postulated that blackleg is a "low sugar disease". Disease incidence was lower in well fertilized cabbage plants than minimally fertilized plants. Organoleptic tests of cabbage cultivars correlated superior flavour and texture in cabbage with a high susceptibility to blackleg. An integrated management strategy is proposed, based on seed treatment with fungicides, the use of container-grown seedlings rather than seedbed transplants, a 3 yr rotation of crucifer lands with non-cruciferous crops, implementation of either deep-ploughing or accelerated biodegradation to eliminate debris, the development of higher levels of horizontal resistance to L. maculans in cruciferous vegetables, application of field fungicides in high risk areas (benzimidazoles or triazoles, or combinations), and the minimization of stress and optimization of host nutrition