Internode elongation pattern and differential response of rice genotypes to varying levels of flood water

Rice plants are damaged during floods by complete or partial submergence. The pattern of expression of rice plant varies with different flood regimes. Accordingly, the morphological and physiological responses of rice genotypes were studied in field and pot experiments under different flood regimes. Wide genetic base lines of Oryza sativa and sub 1 introgressed submergence tolerant were compared in field experiments using principle component analysis. Further, based on internode elongation pattern, two genotypes – Bodikaburi and Pokkali – were selected for a pot experiment to find more on elongation pattern of internodes under different flood regimes. Short-term submergence in minimal water, elongation of blade, sheath, leaf area, DW, number of nodes in primary stem and survival present showed strong positive relationship with shoot length. Number of tillers, leaf area and DW were more affected and decreased during submergence than its non-submergence counterpart. Under different flooding regimes, cvv Bodikaburi and Pokkali exhibited different behaviour in the elongation pattern of the shoot. Partial submergence accelerated elongation of all internodes whereas complete submergence accelerated the top internode. Enhancement of shoot elongation during submergence in water is an escape strategy adopted by rice to resume aerobic metabolism and to improve carbon fixation. This escape strategy varies among genotypes with respect to different flooding regimes. Therefore, breeders should be aware of breeding of rice plants with suitable architecture for different flood- prone environments.

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Metabolite and Phytohormone Profiling Illustrates Metabolic Reprogramming as an Escape Strategy of Deepwater Rice during Partially Submerged Stress

Metabolites ◽

10.3390/metabo10020068 ◽

2020 ◽

Vol 10 (2) ◽

pp. 68 ◽

Cited By ~ 3

Author(s):

Atsushi Fukushima ◽

Takeshi Kuroha ◽

Keisuke Nagai ◽

Yoko Hattori ◽

Makoto Kobayashi ◽

...

Keyword(s):

Shoot Elongation ◽

Metabolic Reprogramming ◽

Isogenic Line ◽

Internode Elongation ◽

Deepwater Rice ◽

Rice Varieties ◽

Escape Strategy ◽

Metabolite Profiles ◽

Glycolysis Pathway

Rice varieties that can survive under submergence conditions respond to flooding either by enhancing internode elongation or by quiescence of shoot elongation. Despite extensive efforts to identify key metabolites triggered by complete submergence of rice possessing SUBMERGENCE 1 (SUB1) locus, metabolic responses of internode elongation of deepwater rice governed by the SNORKEL 1 and 2 genes remain elusive. This study investigated specific metabolomic responses under partial submergence (PS) to deepwater- (C9285) and non-deepwater rice cultivars (Taichung 65 (T65)). In addition, we examined the response in a near-isogenic line (NIL-12) that has a C9285 genomic fragment on chromosome 12 introgressed into the genetic background of T65. Under short-term submergence (0–24 h), metabolite profiles of C9285, NIL-12, and T65 were compared to extract significantly changed metabolites in deepwater rice under PS conditions. Comprehensive metabolite and phytohormone profiling revealed increases in metabolite levels in the glycolysis pathway in NIL-12 plants. Under long-term submergence (0–288 h), we found decreased amino acid levels. These metabolomic changes were opposite when compared to those in flood-tolerant rice with SUB1 locus. Auxin conjugate levels related to stress response decreased in NIL-12 lines relative to T65. Our analysis helped clarify the complex metabolic reprogramming in deepwater rice as an escape strategy.

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Multimodal communication in courting fiddler crabs reveals male performance capacities

Royal Society Open Science ◽

10.1098/rsos.161093 ◽

2017 ◽

Vol 4 (3) ◽

pp. 161093 ◽

Cited By ~ 14

Author(s):

Sophie L. Mowles ◽

Michael Jennions ◽

Patricia R. Y. Backwell

Keyword(s):

Field Experiments ◽

Fiddler Crabs ◽

Vibrational Signal ◽

Sprint Speed ◽

Additional Signal ◽

Additional Information ◽

Waving Display ◽

Redundant Signal ◽

Strong Positive Relationship ◽

Multimodal Signalling

Courting males often perform different behavioural displays that demonstrate aspects of their quality. Male fiddler crabs, Uca sp., are well known for their repetitive claw-waving display during courtship. However, in some species, males produce an additional signal by rapidly stridulating their claw, creating a ‘drumming’ vibrational signal through the substrate as a female approaches, and even continue to drum once inside their burrow. Here, we show that the switch from waving to drumming might provide additional information to the female about the quality of a male, and the properties of his burrow (multiple message hypothesis). Across males there was, however, a strong positive relationship between aspects of their waving and drumming displays, suggesting that drumming adheres to some predictions of the redundant signal hypothesis for multimodal signalling. In field experiments, we show that recent courtship is associated with a significant reduction in male sprint speed, which is commensurate with an oxygen debt. Even so, males that wave and drum more vigorously than their counterparts have a higher sprint speed. Drumming appears to be an energetically costly multimodal display of quality that females should attend to when making their mate choice decisions.

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Influence of Irrigation Regime on Water Relations, Gas Exchange, and Growth of Two Field-grown Redbud Varieties in a Semiarid Climate

Journal of Environmental Horticulture ◽

10.24266/0738-2898.32.1.8 ◽

2014 ◽

Vol 32 (1) ◽

pp. 8-12 ◽

Cited By ~ 1

Author(s):

Lindsey Fox ◽

Amber Bates ◽

Thayne Montague

Keyword(s):

Stomatal Conductance ◽

Gas Exchange ◽

Water Potential ◽

Leaf Area ◽

Shoot Elongation ◽

Sectional Area ◽

Irrigation Regime ◽

Cross Sectional ◽

Area Increase ◽

Irrigation Volume

For three growing seasons (2003–2005) two newly planted, field-grown redbud (Cercis canadensis L.) varieties were subjected to three reference evapotranspiration (ETo)-based irrigation regimes (100, 66, and 33% ETo). Over this time period, water relations (pre-dawn leaf water potential), gas exchange (mid-day stomatal conductance), and growth data (trunk cross sectional area increase, tree leaf area, and shoot elongation) were measured. Pre-dawn leaf water potential (ψl) was more negative for trees receiving the least amount of irrigation, and for Mexican redbud [C. canadensis var. mexicana (Rose) M. Hopkins] trees. However, mid-day stomatal conductance (gs) was similar for Texas redbud (C. canadensis var. texensis S. Watson) trees across the three irrigation regimes, and was highest for Mexican redbud trees receiving the greatest amount of irrigation volume. Growth varied by variety and irrigation regime. Trunk cross sectional area increase was greatest for Mexican redbud trees, leaf area was highest for trees receiving the greatest amount of irrigation, and shoot elongation was greatest for trees receiving the 66% ETo irrigation regime. However, despite differing irrigation volumes, greatest gas exchange and growth was not necessarily associated with greatest irrigation volume. When considering conservation of precious water resources, these redbud varieties maintain adequate growth and appearance under reduced irrigation.

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Water use efficiency of wheat in a Mediterranean-type environment. II. some limitations to efficiency

Australian Journal of Agricultural Research ◽

10.1071/ar9840765 ◽

1984 ◽

Vol 35 (6) ◽

pp. 765 ◽

Cited By ~ 134

Author(s):

RJ French ◽

JE Schultz

Keyword(s):

Water Use Efficiency ◽

Leaf Area ◽

Water Use ◽

Harvest Index ◽

Field Experiments ◽

Field Trials ◽

Growth Yields ◽

Potential Yield ◽

Use Efficiency ◽

Factorial Treatments

Evidence is presented that water use efficiency and yield of wheat are reduced by insufficient leaf area and by inadequate content of nutrients in the top growth. Yields from field trials are compared with the potential yield, and a review is made of the limitations caused by weeds, the incidence of diseases and the harvest index. The data highlight the need for field experiments to define the evaporation and transpiration components of water use in each environment. They also indicate the need for multi-factorial treatments to overcome all yield limitations and thereby attain the potential yield.

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Effect of nitrogen addition on the comparative productivity of corn and velvetleaf (Abutilon theophrasti)

Weed Science ◽

10.1614/ws-05-127r.1 ◽

2006 ◽

Vol 54 (02) ◽

pp. 354-363 ◽

Cited By ~ 14

Author(s):

Darren C. Barker ◽

Stevan Z. Knezevic ◽

Alex R. Martin ◽

Daniel T. Walters ◽

John L. Lindquist

Keyword(s):

Leaf Area ◽

Field Experiments ◽

Yield Loss ◽

Biomass Accumulation ◽

Nitrogen Addition ◽

Corn Yield ◽

N Addition ◽

Area Index ◽

Nitrogen Levels ◽

Weed Growth

Weeds that respond more to nitrogen fertilizer than crops may be more competitive under high nitrogen (N) conditions. Therefore, understanding the effects of nitrogen on crop and weed growth and competition is critical. Field experiments were conducted at two locations in 1999 and 2000 to determine the influence of varying levels of N addition on corn and velvetleaf height, leaf area, biomass accumulation, and yield. Nitrogen addition increased corn and velvetleaf height by a maximum of 15 and 68%, respectively. N addition increased corn and velvetleaf maximum leaf area index (LAI) by up to 51 and 90%. Corn and velvetleaf maximum biomass increased by up to 68 and 89% with N addition. Competition from corn had the greatest effect on velvetleaf growth, reducing its biomass by up to 90% compared with monoculture velvetleaf. Corn response to N addition was less than that of velvetleaf, indicating that velvetleaf may be most competitive at high levels of nitrogen and least competitive when nitrogen levels are low. Corn yield declined with increasing velvetleaf interference at all levels of N addition. However, corn yield loss due to velvetleaf interference was similar across N treatments except in one site–year, where yield loss increased with increasing N addition. Corn yield loss due to velvetleaf interference may increase with increasing N supply when velvetleaf emergence and early season growth are similar to that of corn.

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Can we predict dispersal guilds based on the leaf-height-seed scheme in a disjunct cerrado woodland?

Brazilian Journal of Biology ◽

10.1590/s1519-69842008000300013 ◽

2008 ◽

Vol 68 (3) ◽

pp. 553-559 ◽

Cited By ~ 7

Author(s):

AVF. Jardim ◽

MA. Batalha

Keyword(s):

Leaf Area ◽

Specific Leaf Area ◽

Field Experiments ◽

Plant Traits ◽

Seed Mass ◽

Soil Nutrient ◽

Canopy Height ◽

Southeastern Brazil ◽

Plant Canopy ◽

Frugivorous Birds

Although there have been advances in methods for extracting information about dispersal processes, it is still very difficult to measure them. Predicting dispersal groups using single readily-measured traits would facilitate the emergence of instructive comparisons among ecological strategies of plants and offer a path towards improved synthesis across field experiments. The leaf-height-seed scheme consists of three functional traits: specific leaf area, plant canopy height, and seed mass. We tested, applying logistic regression analysis, whether these traits are potential predictors of dispersal guilds in a disjoint cerrado woodland site in southeastern Brazil. According to our results, none of the plant traits studied could predict dispersal guild; this means that abiotically and biotically dispersed species showed similar values of specific leaf area, height, and seed mass. The species of both guilds exhibited sclerophylly, probably a result of the typical soil nutrient deficiency of cerrado, which also may have placed constraints upon plant canopy height regardless of the dispersal mode. In the cerrado, some abiotically dispersed trees might present higher than expected seed mass as support to the investment in high root-to-shoot ratio at the seedling stage. Seeds of bird-dispersed species are limited in size and mass because of the small size of most frugivorous birds. Since soil nutrient quality might contribute to the similarity between the dispersal guilds regarding the three traits of the scheme, other plant traits (e.g., root depth distribution and nutrient uptake strategy) that detail the former should be considered in future predictive studies.

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Leaf Removal Affects Maize Morphology and Grain Yield

Agronomy ◽

10.3390/agronomy10020269 ◽

2020 ◽

Vol 10 (2) ◽

pp. 269 ◽

Cited By ~ 1

Author(s):

Guangzhou Liu ◽

Yunshan Yang ◽

Wanmao Liu ◽

Xiaoxia Guo ◽

Jun Xue ◽

...

Keyword(s):

Grain Yield ◽

Leaf Area ◽

Field Experiments ◽

Photosynthetic Capacity ◽

Maize Yield ◽

Light Distribution ◽

Planting Density ◽

Leaf Removal ◽

Area Index ◽

Source Sink

Increasing planting density is an important practice associated with increases in maize yield, but densely planted maize can suffer from poor light conditions. In our two-year field experiments, two morphologically different cultivars, ZD958 (less compact) and DH618 (more compact), were planted at 120,000 plants ha−1 and 135,000 plants ha−1, respectively. We established different leaf area index (LAI) treatments by removing leaves three days after silking: (1) control, no leaves removed (D0); (2) the two uppermost leaves removed (D1); (3) the four uppermost leaves removed (D2); (4) the leaves below the third leaf below the ear removed (D3); (5) the leaves of D1 and D3 removed (D4); (6) the leaves of D2 and D3 removed (D5). Optimal leaf removal improved light distribution, increased photosynthetic capacity and the post-silking source-sink ratio, and thus the grain yield, with an average LAI of 5.9 (5.6 and 6.2 for ZD958 and DH618, respectively) for the highest yields in each year. Therefore, less-compact cultivars should have smaller or fewer topmost leaves or leaves below the ear that quickly senesce post-silking, so as to decrease leaf area and thus improve light distribution and photosynthetic capacity in the canopy under dense planting conditions. However, for more compact cultivars, leaves below the ear should senesce quickly after silking to reduce leaf respiration and improve the photosynthetic capacity of the remaining top residual leaves. In future maize cultivation, compact cultivars with optimal post-silking LAI should be adopted when planting densely.

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Estimation of Peanut Leaf Area Index from Unmanned Aerial Vehicle Multispectral Images

Sensors ◽

10.3390/s20236732 ◽

2020 ◽

Vol 20 (23) ◽

pp. 6732

Author(s):

Haixia Qi ◽

Bingyu Zhu ◽

Zeyu Wu ◽

Yu Liang ◽

Jianwen Li ◽

...

Keyword(s):

Leaf Area Index ◽

Leaf Area ◽

Vegetation Index ◽

Field Experiments ◽

Predictive Accuracy ◽

Vegetation Indices ◽

Planting Density ◽

Coefficient Of Determination ◽

Multispectral Images ◽

Area Index

Leaf area index (LAI) is used to predict crop yield, and unmanned aerial vehicles (UAVs) provide new ways to monitor LAI. In this study, we used a fixed-wing UAV with multispectral cameras for remote sensing monitoring. We conducted field experiments with two peanut varieties at different planting densities to estimate LAI from multispectral images and establish a high-precision LAI prediction model. We used eight vegetation indices (VIs) and developed simple regression and artificial neural network (BPN) models for LAI and spectral VIs. The empirical model was calibrated to estimate peanut LAI, and the best model was selected from the coefficient of determination and root mean square error. The red (660 nm) and near-infrared (790 nm) bands effectively predicted peanut LAI, and LAI increased with planting density. The predictive accuracy of the multiple regression model was higher than that of the single linear regression models, and the correlations between Modified Red-Edge Simple Ratio Index (MSR), Ratio Vegetation Index (RVI), Normalized Difference Vegetation Index (NDVI), and LAI were higher than the other indices. The combined VI BPN model was more accurate than the single VI BPN model, and the BPN model accuracy was higher. Planting density affects peanut LAI, and reflectance-based vegetation indices can help predict LAI.

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Early Season Growth, Yield, and Fruit Quality of Standard and Mini Watermelon Grafted onto Several Commercially Available Cucurbit Rootstocks

HortTechnology ◽

10.21273/horttech04051-18 ◽

2018 ◽

Vol 28 (4) ◽

pp. 459-469 ◽

Cited By ~ 6

Author(s):

Matthew B. Bertucci ◽

Katherine M. Jennings ◽

David W. Monks ◽

Jonathan R. Schultheis ◽

Penelope Perkins-Veazie ◽

...

Keyword(s):

Leaf Area ◽

Fruit Quality ◽

Field Experiments ◽

Growth Yield ◽

The United States ◽

Marketable Yield ◽

Early Season ◽

Flesh Firmness ◽

Lycopene Content

Grafting watermelon (Citrullus lanatus) is a common practice in many parts of the world and has recently received increased interest in the United States. The present study was designed to evaluate early season growth, yield, and fruit quality of watermelon in response to grafting and in the absence of known disease pressure in a fumigated system. Field experiments were conducted using standard and mini watermelons (cv. Exclamation and Extazy, respectively) grafted onto 20 commercially available cucurbit rootstocks representing four species: giant pumpkin (Cucurbita maxima), summer squash (Cucurbita pepo), bottle gourd (Lagenaria siceraria), and interspecific hybrid squash [ISH (C. maxima × Cucurbita moschata)]. Nongrafted ‘Exclamation’ and ‘Extazy’ were included as controls. To determine early season growth, leaf area was measured at 1, 2, and 3 weeks after transplant (WAT). At 1 WAT, nongrafted ‘Exclamation’ produced the smallest leaf area; however, at 3 WAT, nongrafted ‘Exclamation’ produced the largest leaf area in 2015, and no differences were observed in 2016. Leaf area was very similar among rootstocks in the ‘Extazy’ study, with minimal differences observed. Marketable yield included fruit weighing ≥9 and ≥3 lb for ‘Exclamation’ and ‘Extazy’, respectively. In the ‘Exclamation’ study, highest marketable yields were observed in nongrafted ‘Exclamation’, and ‘Exclamation’ grafted to ‘Pelops’, ‘TZ148’, and ‘Coloso’, and lowest marketable yields were observed when using ‘Marvel’ and ‘Kazako’ rootstocks, which produced 47% and 32% of nongrafted ‘Exclamation’ yield, respectively. In the ‘Extazy’ study, the highest marketable yield was observed in nongrafted ‘Extazy’, and ‘Kazako’ produced the lowest yields (48% of nongrafted ‘Extazy’). Fruit quality was determined by measuring fruit acidity (pH), soluble solids concentration (SSC), lycopene content, and flesh firmness from a sample of two fruit from each plot from the initial two harvests of each year. Across both studies, rootstock had no effect on SSC or lycopene content. As reported in previous studies, flesh firmness was increased as a result of grafting, and nongrafted ‘Exclamation’ and ‘Extazy’ had the lowest flesh firmness among standard and mini watermelons, respectively. The present study evaluated two scions with a selection of 20 cucurbit rootstocks and observed no benefits in early season growth, yield, or phytonutrient content. Only three of 20 rootstocks in each study produced marketable yields similar to the nongrafted treatments, and no grafted treatment produced higher yields than nongrafted ‘Exclamation’ or ‘Extazy’. Because grafted seedlings have an associated increase in cost and do not produce increased yields, grafting in these optimized farming systems and using fumigated soils does not offer an advantage in the absence of soilborne pathogens or other stressors that interfere with watermelon production.

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Phosphorus and Zinc Fertilization Improve Zinc Biofortification in Grains and Straw of Coarse vs. Fine Rice Genotypes

Agronomy ◽

10.3390/agronomy10081155 ◽

2020 ◽

Vol 10 (8) ◽

pp. 1155

Author(s):

Amanullah ◽

Inamullah ◽

Mona S. Alwahibi ◽

Mohamed Soliman Elshikh ◽

Jawaher Alkahtani ◽

...

Keyword(s):

Management Practices ◽

Field Experiments ◽

Negative Impact ◽

Oryza Sativa L ◽

Crop Productivity ◽

Continuous Cropping ◽

Rice Varieties ◽

Rice Grains ◽

Rice Genotypes ◽

The Impact

Continuous cropping of rice (Oryza sativa L.) and wheat (Triticum aestivum L.) deplete soil fertility and reduce crop productivity as well as zinc (Zn) concentrations in rice grains and straw. Low Zn concentrations in rice grains have a negative impact on human health, while low Zn concertation in rice straw creates a nutritional problem for animals. The current high yielding rice varieties and hybrids remove large quantities of Zn from the soils, lowering the residual concentrations of soil Zn for the subsequent crop (e.g., wheat). Field experiments were conducted on farmers field in Malakand with the objective to evaluate the impact of various combinations of phosphorus (0, 40, 80, and 120 kg ha−1) and Zn levels (0, 5, 10, and 15 kg ha−1) on biofortification of Zn in grains and straw of rice genotypes [fine (Bamati-385) vs. coarse (Fakhre-e-Malakand and Pukhraj)]. The results revealed that Zn biofortification in rice genotypes increased with the integrated use of both nutrients (P + Zn) when applied at higher rates (80 and 120 kg P ha−1, and 10 and 15 kg Zn ha−1, respectively). The biofortification of Zn in both grains and straw was higher in the coarse than fine rice genotypes (Pukhraj > Fakhre-e-Malakand > Basmati-385). It was concluded from this study that the application of higher P and Zn levels increased Zn contents in rice parts (grains and straw) under the rice-wheat system. We also concluded from this study that Zn concentrations in rice grains and straw are influenced by plant genetic factors and Zn management practices.

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