Field evaluation of early vigour for genetic improvement of grain yield in wheat

2002 ◽  
Vol 53 (10) ◽  
pp. 1137 ◽  
Author(s):  
T. L. Botwright ◽  
A. G. Condon ◽  
G. J. Rebetzke ◽  
R. A. Richards

Improved early vigour in wheat (Triticum aestivum L.) has been proposed as an important trait for increasing grain yield through greater water-use efficiency in rainfed, Mediterranean-type environments. Three years of field trials were undertaken in Western Australia at 2 sites, Merredin (low rainfall, 244 mm in the growing season) and Wongan Hills (medium rainfall, 308 mm), to examine the influence of increased early vigour on crop growth and yield. The effect of breeding for greater early vigour was tested in 1998 and 1999 using 3 high vigour and 3 low vigour BC2:F5 lines of the cultivar Amery backcrossed to a 'high vigour' donor. Averaged across environments, the high vigour backcross lines had a 10% increase in early vigour (i.e. leaf area/plant) at 50 DAS compared with the low vigour lines. Differences in yield across environments were associated with variation in total rainfall, rainfall distribution, and soil properties. In the wetter of the 2 years (1999), greater early vigour translated to increased yield of c. 12%, averaged across environments, but there was no difference in yield in either environment in the drier year (1998). Potential deleterious effects of the recurrent parent on yield were eliminated in field trials in 1999 and 2000 by manipulating early vigour through varying grain size (25, 35, or 50 mg) or seeding density (50, 200, or 400 plants/m2) of Amery at sowing. Large grain increased the embryo size and early vigour at 50 DAS in both environments in 1999. This translated to greater biomass production at anthesis and maturity to increase grain yield at Wongan Hills in 1999. In contrast, there was no relationship between grain size, biomass production, and yield at Merredin in 1999 or at either site in 2000. Sowing density treatments also had no effect on yield in 2000. In conclusion, there is potential to increase yield of wheat by selecting for greater early vigour in a wheat breeding program. The expression of vigour in field conditions and the translation of this improvement to higher yields is, however, dependent on the environment. Current yield limitations arising through backcrossing with a high vigour, yet poor yielding donor, need to be addressed.

2003 ◽  
Vol 54 (10) ◽  
pp. 957 ◽  
Author(s):  
A. G. Condon ◽  
F. Giunta

Transient waterlogging during winter and spring reduces wheat yield in many parts of southern Australia. Yield reductions from waterlogging are associated with reduced production and survival of tillers, fewer and smaller fertile tillers, and smaller grain size. Under favourable conditions, wheats that have the tiller-inhibition ('tin') gene produce a lower total number of tillers but a higher proportion of large, productive tillers and larger grains than wheats without this gene. These characteristics of restricted-tillering wheat may contribute to improved yield under transient waterlogging. We compared the growth and yield of the commercial variety Bodallin and 2 Bodallin backcross derivatives containing the 'tin' gene in 8 field trials grown on shallow, duplex soils in 1995 and 1996 at 3 locations in the south-west of Western Australia. Trials were sown at standard (1995) and standard and high (1996) seeding rates. Trial-mean yield ranged from 0.5 to 4.7 t/ha, depending on the occurrence and severity of waterlogging before anthesis and of soil water deficit before and after anthesis. Grain yield of the restricted-tillering (RT) lines averaged only c. 80% of Bodallin. At all sites and seeding rates the RT lines had fewer spikes per m2 (45% fewer, on average) but averaged 44% more grains per spike. In 1996 only, grain weight of the RT lines was 6% greater than of Bodallin. There was no evidence that the relative yield of the RT lines was greater at waterlogged sites than at other sites. Waterlogging reduced the number of fertile spikes of RT lines and of Bodallin to the same relative extent and differences in grains per spike and grain size had little effect on relative yields. Even though harvest index of the RT lines was slightly elevated in some environments, biomass production of the RT lines was low in all environments. We conclude that wheats with the 'tin' gene are unlikely to have a yield advantage under transient waterlogging unless their biomass production can match that of more freely tillering wheats.


2015 ◽  
Vol 153 (8) ◽  
pp. 1353-1364 ◽  
Author(s):  
C. Y. ZHENG ◽  
J. CHEN ◽  
Z. W. SONG ◽  
A. X. DENG ◽  
L. N. JIANG ◽  
...  

SUMMARYTen leading varieties of winter wheat released during 1950–2009 in North China were tested in a free-air temperature increase (FATI) facility. The FATI facility mimicked the local air temperature pattern well, with an increase of 1·1 °C in the daily mean temperature. For all the tested varieties, warming caused a significant reduction in the total length of wheat growth period by 5 days and especially in the pre-anthesis period, where it was reduced by 9 days. However, warming increased wheat biomass production and grain yield by 8·4 and 11·4%, respectively, on an average of all the tested varieties. There was no significant difference in the warming-led reduction in the entire growth period among the tested varieties. Interestingly, the warming-led increments in biomass production and grain yield increased along with the variety release year. Significantly higher warming-led increases in post-anthesis biomass production and 1000-grain weight were found in the new varieties compared to the old ones. Meanwhile, a significant improvement in plant productivity was noted due to wheat breeding during the past six decades, while no significant difference in the length of entire growth period was found among the varieties released in different eras. The results demonstrate that historical wheat breeding might have enhanced winter wheat productivity and adaptability through exploiting the positive effects rather than mitigating the negative impacts of warming on wheat growth in North China.


Agronomy ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1942
Author(s):  
Giovanni Preiti ◽  
Antonio Calvi ◽  
Maurizio Romeo ◽  
Giuseppe Badagliacca ◽  
Monica Bacchi

Over two cropping seasons, 2017/18 and 2018/19, an experimental trial was conducted in a typical cereal-growing environment of the Calabrian hills (southern Italy) to study seeding rate (D) and nitrogen fertilization (N) effects on two barley F1 hybrids (Zoo and Jallon) compared to those of a traditional variety (Lutece), assessing the bio-agronomic response. Barley hybrids, gradually introduced into the principal European countries starting in 2010 as winter forage, currently represent a significant part of the EU internal market. Productive performance was evaluated as grain yield for feed and total biomass for silage and/or biogas production. Research results pointed out the greater performance of barley hybrids compared to conventional varieties in terms of both grain and biomass production. On average, barley hybrids vigour mainly manifested itself through a high tillering and a greater number of ears m−2 compared to those of the conventional variety (+24 and +23%, respectively). Furthermore, barley hybrids were characterized by a greater 1000-kernel weight and hectolitre weight than those of the Lutece variety (conventional variety). A significant increase in grain production was observed, increasing density from D150 to D225 rates (+35% and +33%, respectively) which was followed by a decrease in production shifting from D225 to D300 doses. A significant increase in biomass production was as well highlighted for the two hybrids, shifting from D150 to D225 rates (+26% and +27%, respectively). The applied nitrogen dose highlighted a different behaviour between the hybrids and the conventional variety; in particular, the lowest nitrogen dose (N80) negatively influenced the Lutece variety both in terms of grain and biomass production (−9% and −16%, respectively) while the hybrids showed the best agronomic response even at the lowest dose. On average, with the N80 dose, grain yield of Zoo and Jallon was greater than 20% and 16%, while with the N120 dose grain yield was 9% and 7%, respectively. A similar behaviour was found for biomass yield. It should therefore be emphasized that barley hybrids possess high yielding capacities and that such higher grain production can be achieved in a Mediterranean environment by using a lower seed rate (approximately −25%) and a reduced nitrogen dose (approximately −33%) compared with those commonly applied to conventional varieties.


2019 ◽  
Vol 3 (1) ◽  
pp. 81
Author(s):  
Saroj Thapa ◽  
Khagendra Thapa ◽  
Jiban Shrestha ◽  
Amit Chaudhary

Rice (Oryza sativa L.) is first staple crop of Nepal. The national average yield of rice is less than its potential yield, for which poor agronomic management has been reported as the critical factor. Among various agro-management practices seedling age, seeding density and nitrogen rates significantly affect the growth and yield of rice. The lower seeding density produces the taller plant, more effective tiller, lower sterility and higher grain yield. On the other hand, seedling of older age from higher seeding density gives the lowest yield. Transplanting younger seedling with low seeding density and application of recommended dose of nitrogen gives a higher yield. This article summarizes various effects of seedling age, seeding density and nitrogen rates on plant height, number of effective tillers, number of filled grains, thousand grain weight and grain yield of rice. This information may be useful for maize growers and researchers.


2014 ◽  
Vol 6 (4) ◽  
pp. 166 ◽  
Author(s):  
B. M. Sani ◽  
I. U. Abubakar ◽  
A. M. Falaki ◽  
H. Mani ◽  
M. M. Jaliya

An experiment was conducted to assess the yield and yield components of QPM genotypes to plant population under irrigated conditions in a semi arid ecology of Northern Nigeria. Field trials were conducted at the Irrigation Research Station, Institute for Agricultural Research, Kadawa (11° 39'N, 08° 20'E) and 500 m above sea level) during dry seasons 2007, 2008 and 2009 to study the effect of (Zea mays L.) genotypes (TZE-W Pop X 1368, EV-DT W99 STR and DMR-ESRW), four plant population (33333, 44444, 55555 and 66666 plants ha-1) and three irrigation scheduling (40, 60 and 80 centibars soil moisture tension) on the growth and yield of quality protein maize. A split plot design was used with combinations of genotypes and irrigation regimes assigned to the main plot and plant population assigned to the sub-plot. The treatments were replicated three times. The study revealed that genotype EV-DT W99 STR had significantly higher weight of ears per plant, cob length, cob diameter, number of rows per cob, 100 grain weight, grain yield, shelling percentage and harvest index than the other two genotypes used in the trial. Irrigating at 40 and 60 centibars significantly increased weight of ears per plant, while delayed irrigation significantly depressed total dry matter production. Based on the results obtained in this study, it can be concluded that the use of genotype EV-DT W99 STR, at 60 centibars irrigation scheduling and population of 55,555 plants ha-1 had resulted in good agro-physiological characters of QPM at Kadawa.


2020 ◽  
Vol 2 (1) ◽  
pp. p263
Author(s):  
Shahnaz Parveen ◽  
Mohammad Issak ◽  
Md. Sohanur Rahman ◽  
Fakhar Uddin Talukder ◽  
Shanta Islam

Objective of this study was to examine and evaluate the role of different rates of salicylic acid (SA) as foliar spray on growth and yield performance of BRRI dhan29. The experiment was conducted at Sher-e-Bangla Agricultural University, Bangladesh from November, 2016 to May, 2017 following a randomized complete block design with five rates of SA in six replications. The results showed that the lower rate of SA (upto 0.75 mM) has a positive effect on rice biomass production including effective tiller per hill, filled grain per panicle, grain yield and straw yield. The highest dry matter production at both maximum tillering and panicle initiation stages was found at SA spray rate of 0.5 mM. The highest number of effective tillers per hill (14.7) as well as the highest filled grain (120.4) and grain yield (8.1 t/ha) were found at SA rate of 0.75 mM. However, the maximum biomass production was obtained at SA rate of 0.25 mM. The minimum grain yield (7.0 t/ha) was observed in the control treatment.


1983 ◽  
Vol 101 (3) ◽  
pp. 517-546 ◽  
Author(s):  
J. F. Jenkyn ◽  
M. E. Finney ◽  
G. V. Dyke

SUMMARYExperiments with spring barley in 1975–7 tested fungicides applied to control powdery mildew (tridemorph) or brown rust (benodanil) in factorial combination with six amounts of fertilizer N, applied either to the seed bed soon after sowing, as a later top dressing or half at each time.Powdery mildew was the principal leaf disease in all three years. It tended to be increased by increments of N and by applying the N late but much less consistently in the first two years, when soils were very dry for much of the growing period, than in 1977 when amounts of rain were much closer to the long-term mean. Tridemorph significantly increased the number of ears in 1975, mean number of grains per ear in 1976 and 1000-grain weight in all three years; it gave net increases in grain yield of 0·55, 0·68 and 0·41 t/ha, respectively, in 1975–7. Yield response to increasing amounts of applied N was greatly increased where mildew had been controlled by the use of tridemorph, and was better where the N had been divided into two dressings than where it had been applied as a single dose. In 1975 and 1977 the biggest responses to tridemorph were obtained with late N but in 1976 yield was increased most by tridemorph where the N had been applied to the seed bed.Analyses of samples taken in 1977 showed no significant effect of tridemorph sprays on concentrations of either N, P or K in the green crop. By contrast, analyses of grain samples in 1976 and 1977 showed that amounts of N in grain (mg N/grain) were affected by amounts of applied N and by tridemorph, and that there were interactions between these two factors. Concentrations of N in the grain (% D.M.) were also determined by the effects which these factors had on grain size. At small N rates tridemorph mostly increased grain size so that N concentrations were decreased by the fungicide. At large N rates increases in grain size where tridemorph had been applied were accompanied by increases in the N content of the grain (mg N/grain) so that N concentrations were either unaffected (1976) or were increased (1977) by the fungicide. With 90 kg/ha of applied N the fungicide increased the amount of N/ha removed in grain by over 21 % in each year. The apparent recoveries of N in these plots were increased from 66 to 81 % and from 87 to 105%, respectively, in the two years. Tridemorph had no significant effect on concentrations of P or K in the harvested grain but increased average amounts of these nutrients removed in the grain by 17 and 14%, respectively, in 1976 and by 14 and 7% respectively, in 1977.Examination of black and white, infra-red aerial photographs of the experiments showed that, in each year, the brightness of individual plot images was significantly correlated with grain yield.Complex designs without division into blocks are especially vulnerable to positional variation. Alternative methods of adjusting for such positional variation were compared in analyses of grain yields. The potential improvements in precision which might be achieved by the appropriate use of such analyses, and the difficulties of ensuring that unacceptable subjectivity and bias are not thereby introduced into the analyses, are discussed.


1995 ◽  
Vol 75 (3) ◽  
pp. 605-611 ◽  
Author(s):  
K. M. Volkmar ◽  
C. Chang

Hydrophilic super-absorbent polymers retain large amounts of plant-available moisture and have been promoted for use as soil amendments in drought-prone regions. This controlled-environment study evaluated the capacity of two commercial polymer gels, Grogel and Transorb, to mitigate the effects of recurring moderate water-deficit stress (dry-down to 50% field capacity before rewatering) on growth and yield of barley and canola. Rates of 0.03, 0.12, 0.47 and 1.87 g polymer kg−1 sandy loam soil (1, 4, 16 and 64 times the recommended commercial application rate) were tested. Plants were grown at a soil moisture content of approximately 50% of field capacity. Neither polymer was effective at the commercially recommended rate. Barley and canola grain yields were unaffected at any Grogel rate, and Transorb had no effect on barley grain yield. Grogel at the highest rate enhanced early shoot mass, mature biomass production and grain yield of barley and increased leaf RWC. Canola had greater early and late vegetative biomass, but pod yield was not increased by Grogel at any rate. Transorb was most effective at four times the recommended rate, significantly increasing tiller and fertile spike number and mature biomass production at that rate. Leaf RWC were unaffected by Transorb treatment. Grogel stimulated root growth of barley but had no effect on roots of canola. Both polymers tended to increase consumptive water use. Spatial restriction was found to drastically reduce the water retention of both polymers and limit the absorbency of both polymers in this study. The high rates of polymer required to elicit a crop yield response under relatively mild water-deficit conditions limit the value of these polymers for agricultural field use of the crop species tested. Key words: Barley, canola, drought, hydrophilic polymer, soil conditioner, water stress


2019 ◽  
Vol 52 (2) ◽  
pp. 73-78
Author(s):  
Olusegun Raphael Adeyemi ◽  
David Obaloluwa Hosu ◽  
Patience Mojibade Olorunmaiye ◽  
Adeniyi Adebowale Soretire ◽  
Joseph Aremu Adigun ◽  
...  

Abstract Successful cultivation of maize depends largely on efficient weed control, adequate supply of essential nutrients and sufficient soil moisture. Screenhouse and field trials were conducted at the Teaching and Research Farm of the Federal University of Agriculture, Abeokuta, Nigeria during the early and late cropping season of 2013 to evaluate effects of biochar integrated with manual weeding and pre-emergence herbicides on weed control efficiency and productivity of maize. The screenhouse trial was a 6 × 5 factorial experiment fitted into Completely Randomized Design in three replicates. The two factors were biochar: 0, 2, 4, 6, 8 and 10 t ha−1 and weed control methods: weedy check, hoe weeding at 6 Weeks After Sowing (WAS), hoe weeding at 3, 6, and 9 WAS, pre-emergence herbicide application (Codal Gold) at 1.0 and 2.0 kg a.i./ha−1. The field trial was laid out in split-plot arrangement fitted into Randomized Complete Block Design with three replicates. The three main treatments plots on the field consisted of the optimum rates of biochar obtained in the screenhouse (10 t ha−1) compared with 20 t ha−1 and 0 t ha−1 which served as the control. The sub-plots treatments consisted of weed control methods used in the screen house experiment. Data were collected on grain yield and weed dry matter. The result showed that biochar at 10 and 20 t ha−1 in the screenhouse and field trials, respectively, resulted in significantly (P < 0.05) higher grain yield compared with other rates tested. Highest grain yield was obtained in pots hoe weeded thrice at 3, 6 and 9 WAS. Whereas similar grain yield was recorded in plot weeded once at 6 WAS and that hoe weeded at 3, 6 and 9 WAS in the field experiment. Biochar application of 20 t ha−1 gave optimum maize yield. Among the weed control treatments manual weeding either at 6 WAS or at 3, 6 and 9 WAS recorded the highest grain yields. Therefore, incorporation of biochar with either preemergence herbicide or manual hoe weeding would enhance the growth and yield of maize.


2020 ◽  
Vol 53 (2) ◽  
pp. 73-79
Author(s):  
Joseph Aremu Adigun ◽  
Olusegun Raphael Adeyemi ◽  
Olumide Samuel Daramola ◽  
Patience Mojibade Olorunmaiye

AbstractWeed infestation is one of the major factors attributed for the poor yield of cowpea in Nigeria and other parts of sub-Sahara Africa (SSA). Field trials were therefore conducted to evaluate the effect of row spacing and different weeding levels on weed control, growth and yield of cowpea during the early and late wet seasons of 2009. In both seasons, the use of 60 cm row spacing resulted in significant (P < 0.05) reduction in weed density by 18 – 39% and weed biomass by 17 – 27% with subsequent increase in cowpea growth and grain yield than 75 and 90 cm row spacing. Cowpea grain yield increased by 67 – 109% in the early season and 24 – 56% in the late season at 60 compared to 75 and 90 cm row spacing. Hoe weeding reduced weed growth significantly in both seasons with the lowest weed density and biomass recorded in plots weeded thrice. However, this was not significantly different from weed density and biomass recorded with two weedings in both seasons. Hoe weeding twice resulted in optimum growth and grain yield of cowpea. An additional weeding, however, did not improve cowpea growth and yield in both seasons. The results of this study showed that narrow (60 cm) inter-row spacing and two hoe weedings at 3 and 6 weeks after sowing (WAS) will improve weed control and productivity of cowpea. Additional weeding is considered superfluous.


Sign in / Sign up

Export Citation Format

Share Document