Adaptation of lentil (Lens culinaris Medik) to short season Mediterranean-type environments: response to sowing rates

1998 ◽  
Vol 49 (7) ◽  
pp. 1057 ◽  
Author(s):  
K. H. M. Siddique ◽  
S. P. Loss ◽  
K. L. Regan ◽  
D. L. Pritchard

The growth and seed yield response of lentil (cv. Digger) to sowing rate (20-120 kg/ha) was studied at 13 sites over 3 seasons in the cropping regions of south-western Australia. The economic optimum plant density was estimated by fitting an asymptotic model to the data and calculating the sowing rate above which the cost for additional seed was equivalent to the revenue that could be achieved from the extra seed yield produced, assuming a 10% opportunity cost. On average across all sites and seasons, only 51% of sown seeds emerged. Increasing sowing rate resulted in greater dry matter production at ˚owering and maturity, and fewer pods per plant. Harvest index (0·31-0·36), number of seeds per pod (1·13-1·84), and mean seed weight (2·9-3·6 g/100 seeds) remained relatively stable with changes in sowing rate. The asymptotic models fitted to seed yields accounted for 1-73% of the total variance in the data, except at one site where a model could not be found to provide an adequate fit to the data. In addition to this site, another 5 sites were excluded from further consideration where the percentage of variance accounted for was <25% or the predicted optimum densities and seed yield potentials were well beyond the range of the data. The economic optimum of the remaining 7 sites ranged from 96 to 228 plants/m2, with a mean of 146 plants/m2. These results suggest that lentil yields may be improved by increasing sowing rates beyond those currently targeted in southern Australia (100-125 plants/m2). On the basis of these results, targeting a density of about 150 plants/m2 by using a sowing rate of approximately 90-110 kg/ha is recommended, depending on mean seed weight and germination percentage of the seed. Even higher sowing rates may be optimum where the growing conditions are unfavourable and individual plant growth is limited.

1977 ◽  
Vol 88 (3) ◽  
pp. 605-614 ◽  
Author(s):  
P. D. Hebblethwaite

SUMMARYThe effects of irrigation and nitrogen on S. 23 perennial ryegrass grown for seed were investigated in a series of field experiments from 1972 to 1974. Irrigation significantly increased seed yield by 16% in 1972 and 52% in 1974 but had no effect in the wet year of 1973. In 1972 maximum deficit reached 110 mm at the end of July and coincided with anthesis. Consequently the yield response was due to an increase in number of seeds per unit area and no other seed yield component was affected. In 1974 peak deficit also reached about 100 mm but started to build up rapidly very early in the season and had reached 80 mm by the time that the first ears emerged. Consequently the yield response was due to increases in number of fertile tillers, number of seeds per unit area and 1000-seed weight.Irrigation had no significant effect on number of florets or seeds, except in 1974 when percentage of florets which produced seed was increased by 2%.Irrigation had some effect on threshed straw yields, total dry matter, harvest index and total number of tillers but where this occurred the response was much smaller than that of seed yield which indicates that irrigation had greater effects on the reproductive development of the crop than on yield of dry matter and tillering patterns. Increasing the quantity of nitrogen from 0 to 80 kg/ha increased seed yields, all seed yield components except 1000-seed weight, threshed straw yields and total dry matter and number of tillers at most sampling dates. Increasing the quantity of nitrogen from 80 to 160 kg/ha had little further effect on the above components except in 1972 where seed yields were significantly decreased.In 1972 number of florets was increased and percentage of florets which produced seed decreased with increasing quantities of nitrogen.


1995 ◽  
Vol 35 (4) ◽  
pp. 475 ◽  
Author(s):  
GA Sandral ◽  
BS Dear ◽  
NE Coombes

The effect of broadleaf herbicides on seed set by Trifolium subterraneum (subterranean clover) cultivars was examined at 2 sites (Wagga Wagga and Canowindra) over 2 years. Five commonly used herbicide treatments (bromoxynil, MCPA, 2,4-DB, MCPA + terbutryn, MCPA + diuron) were applied at 2 rates to 7 cultivars of subterranean clover. Significant site x cultivar x herbicide interactions were observed. Seed yields were either unaffected or depressed by up to 66% at the higher rainfall site (Canowindra), whereas at the lower rainfall site (Wagga Wagga) some herbicide x cultivar combinations showed increases in seed yield up to 115%. The increase in seed yield was greater at the lower herbicide rate. The variation in seed yield with herbicide treatment was largely a result of a change (P<0.001) in the number of seeds set (R = 0.94 at Wagga Wagga; R = 0.85 at Canowindra). Seed size was also correlated (P<0.001) with seed yield at both sites but explained less of the variation (R = 0.23 at Wagga Wagga; R = 0.47 at Canowindra). The reduction in herbage yield as a result of herbicide application was a poor indicator of the subsequent seed yield response at both sites. Cultivar Trikkala was consistently most tolerant to the herbicide treatments, showing either no change in seed yield at the wetter site or large increases in seed yield at the lower rainfall site. In contrast, the seed yield of Dalkeith was depressed by 2,4-DB at both sites in both years by 39-66%. Increases in seed yield, which were most pronounced in cultivars of midseason maturity (Trikkala, Junee, Seaton Park) and least in later maturing cultivars (Karridale, Clare) and in the very early flowering Dalkeith, were attributed in part to a water-saving effect of the herbicide treatments. Cultivar maturity ranking was negatively correlated (P<0.001) with seed yield (R=-0.73 at Wagga Wagga; R=-0.45 at Canowindra). The germination percentage of seed produced by the cultivars was unaffected by herbicide treatment, although the number of abnormal radicles formed by germinating seed was higher in the 2,4-DB and MCPA treatments.


2000 ◽  
Vol 80 (4) ◽  
pp. 713-719 ◽  
Author(s):  
Ken J. Kirkland ◽  
Eric N. Johnson

Brassica napus L. canola production on the Canadian prairies often is limited by hot, dry growing conditions in early July and a short growing season. Brassica napus canola seeded in the fall just prior to freeze-up or in the early spring as soon as fields are passable may allow canola to avoid these adverse conditions. Our objective was to determine if late October (fall), or mid- to late April (April) seeding dates improve canola yield and quality relative to a mid-May (15 to 20 May) seeding date. Plant density and height, phenological development, seed yield, seed weight and seed oil content were assessed in plots sown to herbicide-tolerant B. napus canola at three seeding dates on five fallow sites and three stubble sites at Scott, SK, from 1994 to 1998. A thinner plant stand occurred for the fall compared with spring seeding dates; however, this difference rarely corresponded with less canola yield. Fifty percent flowering occurred 20 d earlier (June rather than July), reproductive growth (50% flowering to maturity) was 10 d longer, plants were 23 (fall) or 8 (April) cm shorter, and maturity occurred 13 d earlier when canola was seeded in the fall and April compared with mid-May seeding. Canola seed yield was 38% greater when seeded on the alternative dates rather than the more traditional mid-May seeding date. The yield advantage for alternative seeding dates was greater and more consistent on stubble than on fallow likely because of lack of soil crusting and temperature and wind protection from stubble. The response of seed weight to seeding date was similar to that for seed yield, indicating that a portion of the positive yield response to alternative seeding dates was associated with larger seed size. Oil content also was greater for the fall and April compared with mid-May seeding dates, but the improvement was smaller (6%) than that for seed yield. Fall- and April-seed-ed canola tolerated spring frosts and avoided adversely hot, dry weather during the flowering period, thus improving canola seed yield and quality. Alternative seeding dates provide canola producers in semi-arid regions with a sustainable option to diversify their cropping systems. Key words: Seeding date, dormant, stubble, fallow, herbicide tolerant, alternative cropping practice


2003 ◽  
Vol 43 (1) ◽  
pp. 87 ◽  
Author(s):  
K. L. Regan ◽  
K. H. M. Siddique ◽  
L. D. Martin

The effect of sowing rate (60–320 kg/ha) on the growth and seed yield of kabuli chickpea (cv. Kaniva) was assessed at 11 sites for 4 seasons in the cropping regions of south-western Australia. The economic optimum plant density and yield potential were estimated using an asymptotic model fitted to the data and calculating the sowing rate above which the cost of additional seed was equivalent to the revenue that could be achieved from the extra seed yield produced, assuming a 10 and 50% opportunity cost. On average for all sites and seasons, plant densities ranged from 10 plants/m2 when sown at 60 kg/ha to 43�plants/m2 when sown at 320 kg/ha. Assuming a mean seed weight of 400 mg and a germination of 80%, then on average 75% of viable seeds sown (or 60% of sown seeds) established as plants. The poor establishment rates are thought to be associated with reduced viability caused by mechanical damage, storage conditions, fungal infection in the soil, and unfavourable seed bed moisture and temperatures. In general, there was a positive relationship between sowing rate and seed yield. Seed yield increases at higher sowing rates were mainly associated with the greater number of plants per unit area. There were fewer pods per plant at higher sowing rates, but there were more pods per unit area. Changing the sowing rate had little effect on mean seed weight and the number of seeds per pod. The economic optimum plant density varied from 8 to 68 plants/m2, depending on the location, but the mean (27�plants/m2) was within the range currently recommended in southern Australia (25–35 plants/m2). Due to the low establishment rates observed in this study, we estimate a sowing rate greater (160–185 kg/ha) than currently suggested (110–160 kg/ha) to achieve this density. There was a strong relationship between economic optimum plant density and seed yield potential (r2 = 0.66, P<0.01), which allows an estimation of the most profitable sowing rate, depending on the seed yield potential of the site. For most crops yielding about 1.0 t/ha in southern Australia, a plant density of 25 plants/m2 is most profitable, while in higher-yielding situations (>1.5 t/ha) plant densities >35�plants/m2 will produce the most profit.


1998 ◽  
Vol 49 (6) ◽  
pp. 989 ◽  
Author(s):  
R. Jettner ◽  
S. P. Loss ◽  
L. D. Martin ◽  
K. H. M. Siddique

Sowing rate influences plant establishment, growth, seed yield, and the profitability of a crop. However, there is limited published information on the optimum sowing rate and plant density for faba bean in Australia. The response of the growth and seed yield of faba bean (cv. Fiord) to sowing rate (70-270 kg/ha) was examined in 19 field experiments conducted over 3 years in south-western Australia. The economic optimum plant density was estimated at each site by fitting an asymptotic model to the data and calculating the point where the cost of extra seed equalled the return from additional seed yield, allowing a 10% opportunity cost for the extra investment. On average across all sites and seasons, only 71% of the seeds sown emerged. Increasing sowing rate resulted in more dry matter production at first flower and at maturity, and at about half of the sites there was a small trend of reduced harvest index. In general, the mean number of seeds per pod (1·8-2·6) and mean seed weight (32-45 g/100 seeds) were unaffected by sowing rate. As sowing rate increased, the number of pods per plant (5-35) generally decreased, but this was compensated by the large plant population and more pods per unit area. The asymptotic models fitted to the seed yield data accounted for 15-81% of the variance. In 8 experiments, the models indicated that yield was continuing to increase substantially as sowing rate increased at the largest sowing rate treatment. The estimated optimum plant densities in these experiments were beyond the range of the data or had large standard errors and, hence, were excluded from any further consideration. Among the remaining 11 experiments, the estimated optimum plant densities varied from 31 to 63 plants/m2, with a mean of 45 plants/m2. This study demonstrates that targeting sowing rates greater than the current commercial practice for faba bean in southern Australia of 15-30 plants/m2 results in more yield and profit. Additional experiments are required with sowing rates in excess of 270 kg/ha to estimate accurately the optimum plant density for faba bean. Fungal diseases were either absent or controlled with fungicides in these experiments but the interactions between disease, time of sowing, and sowing rates also deserve further attention.


2017 ◽  
Vol 23 (1) ◽  
Author(s):  
A. B. SAGADE

The study of the effect of three well known mutagens, ethyl methane sulphonate (EMS), methyl methane sulphonate (MMS) and gamma rays (GR) on the yield contributing traits of the urdbean variety TPU-4 were carried out in the M3 generation. Effect of selected mutagenic treatments/doses of EMS (0.02, 0.03 and 0.04 M), MMS (0.0025, 0.05 and 0.01 M) and (GR) (30, 40 and 50 KR) on different yield contributing traits like plant height, plant spread, number of pods per plant, pod length, number of seeds per pod, seed yield per plant and 100 seed weight were analyzed in the M3 populations of the variety TPU-4. Seeds of M2 plants and control were harvested separately and sown to raise M3 population.. Genetic variabilty in the mutagen administered M3 progeny of the urdbean variety TPU-4 was analyzed by employing statistical methods. Data on mean values and shift in the mean of seven quantitative traits was evaluated on individual plant basis. The experimental findings revealed that concentrations / dose of the all these mutagens showed inhibitory effect on plant height, number of pods per plant, pod length and number of seeds per pod. Lower concentrations of mutagens exerted a promotory effect on plant spread, 100 seed weight and seed yield per plant while higher concentrations of these mutagens inhibited them to different extent.


2016 ◽  
Vol 6 (1) ◽  
pp. 39
Author(s):  
Y. Zubairu ◽  
J. A. Oladiran ◽  
O. A. Osunde ◽  
U. Ismaila

Study was conducted in 2006 and 2007 cropping seasons at the experimental field of Federal University of Technology, Minna (9o 401N and 6o 301E), in the Southern Guinea Savanna of Nigeria to determine the effects of N fertilizer and the fruit positions on fruit and seed yield of okro. The treatment comprised factorial combination of five nitrogen levels (0, 30, 60, 90 and 120 kg/ha) and five fruit positions on a mother-plant (3, 5, 7, 9 and 10) which were replicated three times and laid in a Randomized Complete Block Design (RCBD). The results indicated that significant taller plants were recorded in the plots that received 120 kg N/ha while shorter plants were recorded in plots that received 0 N/ha in both years of the study. The higher N level of 120 kg/ha and lower fruit position of 3 significantly gave higher number of fruit yield while the yield decreased with decrease in N level and increase in fruit position on the mother-plant. Similarly, heavier fruits were recorded in lower fruit positions and higher N levels. The fruits formed at the lower position 3 and 5 produced more seeds with higher seed weight than those formed at the higher positions. The results also showed that significantly higher seed yield was recorded at N level of 120 kg/ha ?.


2009 ◽  
Vol 62 ◽  
pp. 343-348 ◽  
Author(s):  
M.P. Rolston ◽  
B.L. McCloy ◽  
I.C. Harvey ◽  
R.W. Chynoweth

A summary of seed yield data from 19 fungicide trials in perennial and hybrid ryegrass (Lolium spp) seed crops conducted over a 12 year period is presented Seed yields from the best fungicide treatments were increased on average by 25 in forage ryegrass (390 kg/ha) and 42 in turf ryegrass (580 kg/ha) Seed yield increases were associated with the control of stem rust and/or maintaining green leaf area during seed fill In turf ryegrass (susceptible to stem rust) delaying the first fungicide application until stem rust appeared resulted in seed yields that were not different (P>005) from the untreated experimental controls whereas early fungicide applications from the beginning of reproductive development increased seed yield by between 36 and 42 Fungicide mixes of a triazole plus a strobilurin usually gave higher seed yields than using either fungicide type alone


2019 ◽  
Vol 111 (4) ◽  
pp. 1923-1932 ◽  
Author(s):  
Walter D. Carciochi ◽  
Rai Schwalbert ◽  
Fernando H. Andrade ◽  
Geomar M. Corassa ◽  
Paul Carter ◽  
...  

1976 ◽  
Vol 56 (3) ◽  
pp. 487-491 ◽  
Author(s):  
S. SMOLIAK ◽  
A. JOHNSTON

Forage and seed yield, percentage seed germination, speed of germination index, and 1,000-seed weight were determined for a population of 170 plants selected from Oxley cicer milkvetch (Astragalus cicer L.). Seedlings from open-pollinated seed from the selected plants were measured for leaf weight and leaf area, and specific leaf weight was calculated. Most of the characters studied were asymmetrical in distribution. The correlation coefficient between forage and seed yields of mature plants was positive and highly significant. Seedling leaf weight was positively and closely related to seedling leaf area, but seedling leaf area was a more reliable indicator of photosynthetic efficiency. The variability in the characters studied in the selected population suggests that further improvement in forage yield, germination percentage, speed of germination, and seedling vigor may be obtained through a breeding program.


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