Vertical Profile of Leaf Senescence during the Grain-Filling Period in Older and Newer Maize Hybrids

Crop Science ◽  
2004 ◽  
Vol 44 (3) ◽  
pp. 827 ◽  
Author(s):  
Oscar R. Valentinuz ◽  
Matthijs Tollenaar
Keyword(s):  
Leaf Senescence ◽  
Vertical Profile ◽  
Grain Filling ◽  
Maize Hybrids ◽  
Grain Filling Period

EFFECT OF SOURCE-SINK RATIO ON DRY MATTER ACCUMULATION AND LEAF SENESENCE OF MAIZE

1982 ◽  
Vol 62 (4) ◽  
pp. 855-860 ◽  
Author(s):  
M. TOLLENAAR ◽  
T. B. DAYNARD
Keyword(s):  
Growth Rate ◽  
Leaf Senescence ◽  
Dry Matter ◽  
Grain Filling ◽  
Crop Growth ◽  
Dry Matter Accumulation ◽  
Crop Growth Rate ◽  
Maize Hybrids ◽  
Grain Filling Period ◽  
Source Sink

The effect of source-sink ratio (i.e., the ability of the leaves to produce photosynthate versus the capacity of the grain to accommodate the assimilates) on dry matter accumulation and leaf senescence during the grain filling period of two short-season maize (Zea mays L.) hybrids was investigated in 1979 and 1980. Source-sink ratio of the maize hybrids was altered by ear removal at midsilking and at 3 wk after midsilking; by partial fertilization of the topmost ear so that treatment ears contained approximately 50% of kernel number of the control; and by removal of all leaf blades but that of the ear leaf at 2 wk after midsilking. Crop growth rate during the period from 3–5 wk after midsilking was reduced by 30% for the partly fertilized treatment and by 60% for both ear removal treatments. During the period from 5 to 7 wk after midsilking, the treatment-by-hybrid interaction for crop growth rate reflected different patterns of leaf senescence. In one hybrid, treatments which caused reductions in sink size delayed leaf senescence and increased the crop growth during the 5 to 7-wk postsilking interval, relative to the control. The reverse was evident for the other hybrid. Partial defoliation tended to cause the remaining ear leaf to senescence slightly earlier than in the control. Apparently two types of leaf senescence occurred: senescence due to assimilate starvation, and senescence due to excessive assimilate accumulation. The former caused by excessively low source-sink ratio and the latter caused by excessively high source-sink ratio. These results indicate that a delicate balance exists between sink and source during the grain-filling period of maize, and that disturbance of this balance can cause substantial yield reductions, plus an acceleration of leaf senescence and maturation processes.

Effect of PASP-KT-NAA on Leaf Senescence and Grain Filling Rate during the Grain-Filling Period in Different Temperature Zones

2013 ◽  
Vol 38 (9) ◽  
pp. 1698-1709
Author(s):  
Tian-Jun XU ◽  
Zhi-Qiang DONG ◽  
Jiao GAO ◽  
Chuan-Xiao CHEN ◽  
Liu JIAO ◽  
...  
Keyword(s):  
Leaf Senescence ◽  
Grain Filling ◽  
Filling Rate ◽  
Grain Filling Rate ◽  
Grain Filling Period

scholarly journals Paclobutrazol Application Favors Yield Improvement of Maize Under Semiarid Regions by Delaying Leaf Senescence and Regulating Photosynthetic Capacity and Antioxidant System During Grain-Filling Stage

Agronomy ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 187 ◽  
Author(s):  
Muhammad Kamran ◽  
Shakeel Ahmad ◽  
Irshad Ahmad ◽  
Izhar Hussain ◽  
Xiangping Meng ◽  
...  
Keyword(s):  
Grain Yield ◽  
Leaf Senescence ◽  
Photosynthetic Rate ◽  
Grain Filling ◽  
Yield Improvement ◽  
Chlorophyll Contents ◽  
Maize Seeds ◽  
Kernel Weights ◽  
Ros Burst ◽  
Grain Filling Period

In the present study, we examined the potential role of paclobutrazol in delaying leaf senescence, in causing changes in the activities of antioxidants, and in the maintenance of photosynthetic activity during the senescence process, and, therefore, on the grain yield of maize under semiarid field conditions. Maize seeds were pretreated with 0 (CK), 200 (PS1), 300 (PS2), and 400 (PS3) mg paclobutrazol L−1. Our results indicated that elevated levels of reactive oxygen species (ROS) and higher accumulation of malondialdehyde (MDA) contents were positively associated with accelerated leaf senescence during the grain-filling periods. The leaf senescence resulted in the disintegration of the photosynthetic pigments and reduced the net photosynthetic rate after silking. However, the resultant ROS burst (O2− and H2O2) was lessened and the leaf senescence and chlorophyll degradation were evidently inhibited in leaves of paclobutrazol-treated maize plants, which was strongly linked with upregulated activities of antioxidant enzymes in treated plants. The enhanced chlorophyll contents and availability of a greater photosynthetic active green leaf area during the grain filling period facilitated the maintenance of higher photosynthetic rate, and light-harvesting efficiency of photosynthesis associated with photosystem II (PSII) resulted in higher kernel number ear−1 and thousand kernel weights, and thus increased the final grain yield. The average maize grain yield was increased by 18.8% to 55.6% in paclobutrazol treatments, compared to untreated control. Among the various paclobutrazol treatments, PS2 (300 mg L−1) treatment showed the most promising effects on enhancing the activities of antioxidative enzymes, delaying leaf senescence and improving the yield of maize. Thus, understanding this effect of paclobutrazol on delaying leaf senescence introduces new possibilities for facilitating yield improvement of maize under semiarid conditions.

scholarly journals Yield Loss Potential of Phaeosphaeria Leaf Spot of Maize Caused by Phaeosphaeria maydis in the United States

Plant Disease ◽  
2005 ◽  
Vol 89 (9) ◽  
pp. 986-988 ◽  
Author(s):  
M. L. Carson
Keyword(s):  
United States ◽  
Leaf Spot ◽  
Grain Filling ◽  
The United States ◽  
Kernel Weight ◽  
Maize Hybrids ◽  
Growing Seasons ◽  
Kernel Weights ◽  
Grain Filling Period ◽  
Southern Florida

The ability of Phaeosphaeria leaf spot (PLS) to reduce yields of maize was evaluated over two winter growing seasons in southern Florida. Nine commercial maize hybrids, varying in reaction to PLS, were planted in a split-plot design with hybrids as whole plots and inoculated versus uninoculated treatments as subplots. The most susceptible hybrid, Pioneer brand 3489, sustained a significant reduction in grain yield (11 to 13%) and 400-kernel weight (5 to 10%) in the trials. Regression analyses indicated that grain yields and 400-kernel weights were reduced 0.23 and 0.16%, respectively, for each percent increase in PLS severity at the mid-dent stage. Because most U.S. maize hybrids are resistant, and PLS develops late in the grain-filling period, its potential to cause substantial losses in the United States appears limited at this time.

The growth of maize: III. The effect of date of sowing and bitumen mulch on dry-matter yields

1975 ◽  
Vol 85 (2) ◽  
pp. 271-279 ◽  
Author(s):  
D. M. Osafo ◽  
G. M. Milbourn
Keyword(s):  
Dry Matter ◽  
Grain Filling ◽  
Secondary Source ◽  
High Radiation ◽  
Maize Hybrids ◽  
Grain Yields ◽  
Resultant Increase ◽  
Net Assimilation ◽  
Grain Filling Period ◽  
Late Sowing

SUMMARYExperiments are described which analyse the effects of date of sowing and of a black petroleum soil mulch on the growth of two maize hybrids. The two hybrids used were Anjou 210, which is late maturing in S.E. England, and Kelvedon 75A, which is an early hybrid.As sowing was delayed from mid-April until the end of May, so there was a greater development of vegetative tissue (mainly stem) and leaf area which reached peaks at a later stage after silking. In Anjou 210 early sowing led to higher grain yields (12%) as the production of peak vegetative weight near to the time of silking allowed dry matter produced after that stage, still at a time of high radiation, to move direct to the oars. Also, the remobilization of the secondary source of grain dry matter, namely previously stored photosynthate from the stem, occurred earlier with early sowing and to a greater extent when a longer grain-filling period was allowed.The hybrid K 75A had a lower vegetative weight, and earlier silking coincided with higher levels of radiation, and the resultant increase in net assimilation rate led to a higher proportion of dry matter being partitioned into the ear. Because this hybrid flowered and senesced early, reserves of stem carbohydrate were low and the time available to transfer carbohydrate to the ear was short, resulting in lower yields than in the later maturing Anjou 210. K 75A also responded unexpectedly to the sowing treatments. Although late sowing gave higher grain yields in both hybrids up to 156 days after sowing, in the case of K 75 A, the early senescence curtailed the continuation of grain fill that would normally give early sowing an advantage and hence the late sown K 75 A produced 10 % more grain.The application of a black petroleum mulch to the surface of the soil to raise soil temperature enhanced the benefits derived from early sowing. Plants given this treatment produced greater leaf areas and vegetative dry weights. As a result more carbohydrate was translocated from the stem during the grain-filling period, increasing grain yield by 13% following an increase in both number of grains and individual grain weight.

scholarly journals Elevated ozone reduces photosynthetic carbon gain by accelerating leaf senescence of inbred and hybrid maize in a genotype-specific manner

2017 ◽  
Author(s):  
Craig R. Yendrek ◽  
Gorka Erice ◽  
Christopher M. Montes ◽  
Tiago Tomaz ◽  
Crystal A. Sorgini ◽  
...  
Keyword(s):  
Leaf Senescence ◽  
Physiological Mechanism ◽  
Grain Filling ◽  
Carbon Gain ◽  
Elevated Ozone ◽  
Free Air ◽  
Maize Genotypes ◽  
Grain Filling Period ◽  
Hybrid Maize ◽  
Hybrid Lines

ABSTRACTExposure to elevated tropospheric ozone concentration ([O3]) accelerates leaf senescence in many C3 crops. However, the effects of elevated [O3] on C4 crops including maize (Zea mays L.) are poorly understood in terms of physiological mechanism and genetic variation in sensitivity. Using Free Air gas Concentration Enrichment (FACE), we investigated the photosynthetic response of 18 diverse maize inbred and hybrid lines to season-long exposure to elevated [O3] (~100 nL L−1) in the field. Gas exchange was measured on the leaf subtending the ear throughout the grain filling period. On average over the lifetime of the leaf, elevated [O3] led to reductions in photosynthetic CO2 assimilation of both inbred (-22%) and hybrid (-33%) genotypes. There was significant variation among both inbred and hybrid lines in the sensitivity of photosynthesis to elevated [O3], with some lines showing no change in photosynthesis at elevated [O3]. Based on analysis of inbred line B73, the reduced CO2 assimilation at elevated [O3] was associated with accelerated senescence decreasing photosynthetic capacity, and not altered stomatal limitation. These findings across diverse maize genotypes could advance the development of more ozone tolerant maize, and provide experimental data for parameterization and validation of studies modeling how O3 impacts crop performance.

Carbon and nitrogen allocation and grain filling in three maize hybrids differing in leaf senescence

2006 ◽  
Vol 24 (3) ◽  
pp. 203-211 ◽  
Author(s):  
B. Pommel ◽  
A. Gallais ◽  
M. Coque ◽  
I. Quilleré ◽  
B. Hirel ◽  
...  
Keyword(s):  
Leaf Senescence ◽  
Grain Filling ◽  
Nitrogen Allocation ◽  
Maize Hybrids ◽  
Carbon And Nitrogen ◽  
Carbon And Nitrogen Allocation

Influence of Canopy Temperature (CT) During Grain-Filling Period on Yield and Effects of Several CT-Associated SSR Loci

2015 ◽  
Vol 41 (4) ◽  
pp. 548 ◽  
Author(s):  
Dong-Ling ZHANG ◽  
Hong-Na ZHANG ◽  
Chen-Yang HAO ◽  
Lan-Fen WANG ◽  
Tian LI ◽  
...  
Keyword(s):  
Canopy Temperature ◽  
Grain Filling ◽  
Ssr Loci ◽  
Grain Filling Period
Sign in / Sign up

Export Citation Format

Share Document