Induced variation for post-emergence herbicide tolerance in lentil.

2021 ◽  
pp. 220-225
Author(s):  
Sarvjeet Singh ◽  
S. R. Sharma ◽  
R. K. Gill ◽  
Shiv Kumar

Abstract Lentil (Lens culinaris L. Medik.) is an important cool-season food legume but is a poor competitor to weeds because of a slow early growth rate. If weeds are left uncontrolled, they can reduce yield by up to 50%. Sensitivity of lentil to post-emergence herbicides warrants development of herbicide-tolerant cultivars. In the absence of natural variability, mutation breeding is a powerful tool to create variability for desired traits. Thus, 1000 seeds of a lentil genotype, LL1203, were exposed to gamma radiation (300 Gy, 60Co) with the objective to induce herbicide tolerance. Seeds of all 530 surviving M1 plants were harvested individually and divided in two parts to raise the M2 generation in two different plots. Each plot was sprayed with imazethapyr (75 g/ha) and metribuzin (250 g/ha) herbicides 50 days after sowing, using water at 375 l/ha. Data on herbicide tolerance for individual M2 plants were recorded after 14 days of herbicide spray on a 1-5 scale, where 1 = highly tolerant (plants free from chlorosis or wilting) and 5 = highly sensitive (leaves and tender branches completely burnt). For herbicide-tolerant M2 plants, data were also recorded for pod and yield per plant. None of the M2 plants showed a high level of tolerance to imazethapyr. However, 14 mutants having higher herbicide tolerance to metribuzin were selected. Two mutants ('LL1203-MM10', 'LL1203-MM7') recorded < 2.0 score, while six mutants recorded < 2.50 score as compared with the 3.13 score of the parent variety. The pods per plant and seed yield per plant of mutants 'LL1203-MM7' (383 and 12.4 g) and 'LL1203-MM10' (347 and 12.1 g) were higher than those of the parent genotype LL1203 (253 and 7.8 g). The study indicated that metribuzin-tolerant mutants have some other desirable traits that can be of use in lentil breeding.

1993 ◽  
Vol 73 (4) ◽  
pp. 985-994 ◽  
Author(s):  
G. Saindon ◽  
G. B. Schaalje

Genotype × environment (GE) effects in regional registration trials for dry beans in western Canada were studied to determine whether geographic distribution of sites could be rationalized. The structure of the GE effects on the maturity, seed weight and seed yield of seven dry bean check cultivars grown at eight locations during 4 yr was investigated using GE mean squares decomposition, cluster analysis and the additive main effect and multiplicative interaction (AMMI) method. The analyses revealed a high level of redundancy in the locations which suggested that most GE effects can be captured with fewer testing sites. The partition of the GE mean squares demonstrated the possibility of reproducing the GE structure of the entire data sets with as few as three sites; however, more locations may be needed to compensate for unpredictable environmental effects. Based on biological interpretation of groupings and visual assessment of the AMMI displays, a five-location set fully represented the GE effects on maturity, seed weight and seed yield and accounted for the inconsistent clustering of the Brooks site for the three traits. Also, the set should allow for site losses due to unpredictable environmental events. The dry bean industry in western Canada is expanding to non-traditional growing areas and the establishment of trials in these areas should be considered as they may create GE effects not considered to date. Key words: Phaseolus vulgaris L., genotype × environment interactions, cluster analysis, AMMI analysis


1984 ◽  
Vol 63 (3) ◽  
pp. 586-588
Author(s):  
THOMAS W. FOX ◽  
J. ROBERT SMYTH

2011 ◽  
Vol 1 (6) ◽  
pp. 260-267
Author(s):  
Reza Talebi ◽  
Ezzat Karami

The morpho â€physiological traits associated with seed yield in chickpea (Cicerarietinum L.) were evaluated on thirty five chickpea genotypes under twodifferent water regimes. In optimum condition, the highest correlation wasbelonged to number of seeds/plant and number of pods/plant (0.944**) andin water deficit condition, the strongest correlation of seed yield was observedwith number of seeds/plant (0.875**), number of pods/plant(0.789**) and 100  â€seed weight (0.438**). Physiological traits (RWC, Chlorophylland Carotenoid) indicated low and positive correlation with yield, buthigh positive correlation with other seeds yields related traits in optimumcondition while, under water deficit condition, chlorophyll content and RWChad low and non â€significant negative correlation with seeds yield. Carotenoid,number of seeds/plant and 100 â€seed weight showed more direct positiveeffect on yield in optimum environment and in stress condition, numberof seeds/ plant and 100 â€seed weight showed highest direct effect on seedyield. Results of factor analysis showed that four factors explained 88.54%and 34.5% of the total variance caused in the characters in optimum andwater deficit environment, respectively. In general, the results suggestedthat a chickpea cultivar, for increased yield under non â€stress conditions,should have maximum number of seeds and pods per plant and under stressconditions should have maximum number of seeds and pods per plant andalso keep the high level of RWC and chlorophyll content in their leaves. Thus,identifying these traits as selection criteria in chickpea breeding programmay be useful for breeders to introduce suitable drought resistant chickpeacultivars for arid regions.


1992 ◽  
Vol 6 ◽  
pp. 245-245
Author(s):  
Sean H. Rice

The shape of an isometric gastropod shell can be described completely by specifying the pattern of shell secretion around the aperture (relative to aperture size) and the growth rate of the aperture itself. These descriptors provide a “natural” morphometric in that they correspond to the specific biological processes involved in constructing the shell.Describing shell form in this way allows us to specify what developmental changes must occur during the transition of one shell form to another. In particular, we can distinguish between transitions that can occur through purely heterochronic processes (changes in growth rate) and those that require a change in the specific pattern in which cells of the mantle lay down shell. We can also investigate just what changes occur during the ontogeny of non-isometric shells.Any change in either the pattern of shell secretion or the growth rate of the animal leads to changes in a number of classical morphometric measures, such as apex angle and whorl expansion rate. Those transformations resulting from changes in growth rate, however, are much more predictable than those resulting from changes in the pattern of shell production. A slight increase in the growth rate of the animal, for instance, produces a correspondingly slight increase in the apex angle and the rate of whorl expansion. By contrast, the consequences of a slight change in the pattern of shell production are highly sensitive to just how that change was achieved.Data from 8 genera of marine snails show that the variance within each genus, relative to the variance among all genera, is smaller for measures of aperture shape (which can only be altered through a change in the pattern of secretion of shell material) than for characters that can change through heterochronic transformations (such as apex angle). Furthermore, the shell forms of a number of non isometric shells can be described by a constant pattern of shell production and a variable growth rate.Heterochronic changes thus appear to be the preferred mechanism for changing phenotype in gastropod shells. Those characters that can only be altered by changing the pattern of shell production around the mantle, such as aperture shape, appear to be more conservative than those that can be changed through purely heterochronic transitions. This is consistent with the idea that mutations which alter many characters in a highly correlated manner have a higher probability of being favored by selection than those with relatively unpredictable consequences.


2014 ◽  
Vol 30 (1) ◽  
pp. 1-13 ◽  
Author(s):  
M. Sahraei

Continuous genetic selection and improvement in nutrition have led to a very fast growth rate in modern strains of broiler chickens. Metabolic disorders such as ascits, sudden death syndrome and leg problems are related to a rapid early growth rate in poultry, especially in broilers, and their incidence can be decreased by slowing early growth. The use of management tools to reduce metabolic disorders that rely primarily on decreasing feed consumption, The feed restriction programs is on of the main techniques in growth curve manipulation for increasing production efficiency in broiler chicken in alleviate the incidence of some metabolic disorders and can be used to reduction the unfavorable effects of fast growth rate in broiler chicken production industry, and could be profitable in broiler chickens production efficiency. This article implicated on new findings in about different feed restriction programs effects on these problems in broiler chickens.


2020 ◽  
Vol 26 (2) ◽  
Author(s):  
Ajey Karan Chaudhari ◽  
Anand Prakash Singh ◽  
B R Chaudhary

Mutation breeding like in other plants can significantly strengthen medicinal plants breeding programs and help to produce novel varieties with higher yield potential and improved yield quality. The dry and healthy seeds of P. corylifolia IC 111228 were subjected to mutagenic treatments namely ethyl methane sulphonate (EMS) and sodium azide (SA). The treatment concentrations 15mM, 30mM, 45mM and 60mM of EMS and 1mM, 2mM, 3mM and 4mM of SA were chosen to evaluate the mutagenic potential in either case. The morphological traits were evaluated in M1 generation viz. plant height, days to flowering initiation, seed yield/plant and 100-seed weight. In EMS treatment 15 mM increased the plant height and seed yield, while in SA treatment 4 mM increased the seed yield/plant and 100-seed yield.


1959 ◽  
Vol 53 (1) ◽  
pp. 78-101 ◽  
Author(s):  
A. J. Brookes ◽  
John Hodges

1. The sources of calves for rearing for beef are discussed and the dependence of the beef industry upon the dairy industry demonstrated.2. An experiment designed to compare the effects of four levels of feeding on the growth rate, conformation, economy of food conversion and type of carcase produced, of three breeds of spring-born steers, Hereford, Dairy Shorthorn and Friesian, is described. The levels of feeding are high or moderate in the calf stage, each followed by high or moderate feeding in subsequent winters.3. The results on growth and time of fattening are given and discussed.4. The calves fed on a high level were almost twice the weight of those fed on a moderate level at 8 months old.5. The well-reared calf had an advantage over the moderately reared calf for the rest of its life.6. Although calves which had been reared moderately showed a marked improvement in growth rate when subsequently fed on a higher level they did not reach the weight of calves fed well throughout at 2 years old.7. The level of feeding in the calf stage had little effect upon the time of fattening provided that the level of feeding in the winter periods of subsequent life was on a high level.8. When subsequent feeding was on a moderate level in the winter months, the calf reared well initially fattened on grass a year earlier than the moderately reared animal.9. The high-moderate treatment is shown to be the most satisfactory from many points of view. On this treatment a minimum of concentrates is used in the production of beef.10. The moderate-moderate cattle may be too heavy for present-day requirements when finished off grass at 3½ years old.11. Cattle which were fed on a high level in winter from 8 to 14 months put on less live weight in the following summer than those fed moderately. A live-weight gain of about 1 lb. a day in winter would appear to be satisfactory if the cattle are to make good use of grass in the following summer.12. These main feeding treatment effects applied to the three breeds used.13. The Friesians were heavier than Dairy Shorthorns or Herefords as calves, and the live weight at most ages was in descending order Friesians, Dairy Shorthorns, Herefords.14. The growth rate of Friesian steers was higher than that of the other two breeds at most stages of life, but the difference between Dairy Shorthorns and Herefords was negligible.15. The Herefords finished earlier than the Dairy Shorthorns and Friesians when fattened in yards or on grass.16. There was some indication (Brookes, 1954) that husk and ringworm caused less trouble with cattle which had been well reared than with those moderately reared.


1994 ◽  
Vol 353 ◽  
Author(s):  
Narasi Sridhar ◽  
Darrell Dunn ◽  
Gustavo Cragnolino

AbstractLocalized corrosion in aqueous environments forms an important bounding condition for the performance assessment of high-level waste (HLW) container materials. A predictive methodology using repassivation potential is examined in this paper. It is shown, based on long-term (continuing for over 11 months) testing of alloy 825, that repassivation potential of deep pits or crevices is a conservative and robust parameter for the prediction of localized corrosion. In contrast, initiation potentials measured by short-term tests are non-conservative and highly sensitive to several surface and environmental factors. Corrosion data from various field tests and plant equipment performance are analyzed in terms of the applicability of repassivation potential. The applicability of repassivation potential for predicting the occurrence of stress corrosion cracking (SCC) and intergranular corrosion in chloride containing environments is also examined.


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