Divergent Leaf Morpho-Physiological and Anatomical Adaptations of Four Lettuce Cultivars in Response to Different Greenhouse Irradiance Levels in Early Summer Season

Lettuce (Lactuca sativa L.) is a winter-spring leafy vegetable, but the high demand for fresh products available year-round requires off-season production. However, the warm climate of the Mediterranean areas can impair the summer production of lettuce, thus requiring the adoption of genotypes tolerant to high irradiance as well as useful agronomic strategies like shading net installations. The aim of our research was to assess the leaf morpho-physiological and anatomical changes, in addition to productive responses, of four lettuce cultivars (‘Ballerina’, ‘Maravilla De Verano Canasta’, ‘Opalix‘, and ‘Integral’) grown under shading and non-shading conditions to unveil the adaptive mechanisms of this crop in response to sub-optimal microclimate (high irradiance and temperature) in a protected environment. Growth and yield parameters, leaf gas exchanges, chlorophyll fluorescence and morpho-anatomical leaf traits (i.e., leaf mass area, stomatal density and epidermal cell density) were determined. Under shading conditions, the fresh yields of the cultivars ‘Ballerina’, ‘Opalix’ (‘Oak leaf’) and ‘Integral’ (‘Romaine’) increased by 16.0%, 26.9% and 13.2% respectively, compared to non-shading conditions while both abaxial and adaxial stomatal density decreased. In contrast, ‘Canasta’ under non-shading conditions increased fresh yield, dry biomass and instantaneous water use efficiency by 9.6%, 18.0% and 15.7%, respectively, while reduced abaxial stomatal density by 30.4%, compared to shading conditions. Regardless of cultivar, the unshaded treatment increased the leaf mass area by 19.5%. Even though high light intensity and high temperature are critical limiting factors for summer lettuce cultivation in a protected environment, ‘Canasta’ showed the most effective adaptive mechanisms and had the best production performance under sub-optimal microclimatic conditions. However, greenhouse coverage with a white shading net (49% screening) proved to be a suitable agricultural practice that ensured an adequate microclimate for the off-season growth of more sensitive cultivars ‘Ballerina’, ‘Oak leaf’ and ‘Romaine’.

Download Full-text

Pores versus spores: competition between photosynthesis and reproduction is constrained by leaf mass per unit area (LMA) in ferns

Biological Journal of the Linnean Society ◽

10.1093/biolinnean/blaa189 ◽

2020 ◽

Author(s):

K G Srikanta Dani ◽

Jose Mathew ◽

T M Nila-Mohan ◽

Raju Antony ◽

S Suresh ◽

...

Keyword(s):

Life Histories ◽

Resource Constraints ◽

Time Window ◽

Unit Area ◽

Stomatal Density ◽

High Fertility ◽

Leaf Lifespan ◽

Trade Off ◽

Terrestrial Species ◽

Leaf Mass

Abstract Diversity in plant life histories is primarily that found in the rate and duration of photosynthetic (vegetative) and reproductive growth. However, direct evidence for an anticipated trade-off between photosynthesis and reproduction is lacking in any plant lineage. Ferns allocate leaf space and resources to both photosynthesis and reproduction, potentially leading to competition for leaf resources between stomatal pores and reproductive spores. We hypothesized that a trade-off between stomatal density (StD; a proxy for photosynthetic capacity) and sporangial density (SpD; a measure of fertility) has evolved in monomorphic ferns due to the common space, time and resource constraints imposed by a highly conserved and globally low leaf mass per unit area (LMA) in ferns, where any increase in LMA indicated greater construction cost and longer leaf lifespan. We measured LMA, StD and SpD in 40 fern species in India that represented both monomorphic and dimorphic conditions from both terrestrial and epiphytic habits. Both StD and SpD showed a 50-fold range in monomorphic species whereas LMA was more conserved (six-fold range). LMA of terrestrial ferns was significantly lower than that of epiphytic ferns. Linear regression between LMA and StD was significantly positive in dimorphic terrestrial ferns (showing the lowest LMA among all ferns) and significantly negative in monomorphic epiphytic ferns (showing the highest LMA among all ferns). Dimorphic terrestrial ferns were highly fecund on their fertile leaves and showed a significantly higher StD to LMA ratio on their sterile leaves compared to monomorphic terrestrial ferns. Dimorphic ferns seem to maximize both StD and SpD by physical separation of photosynthesis and reproduction, and their characteristically low LMA (shorter leaf lifespan = smaller time window) potentially selects for high StD and high fertility. The regression between StD and SpD in monomorphic ferns was significantly linear and positive, although comparisons among closely related species (within families) showed negative correlations when both StD and SpD were high, captured also by a significant quadratic regression between StD and SpD in monomorphic ferns. Monomorphic terrestrial species bearing more spores per stomata showed relatively low LMA whereas those producing fewer spores per stomata possessed leaves with relatively high LMA. Monomorphic epiphytes produced as many spores as terrestrial species but showed significantly low StD for their high LMA. We discuss the evolutionary reasons behind these trends and conclude that monomorphic terrestrial ferns with high LMA (long leaf lifespan) tend to prioritize photosynthesis over reproduction, while monomorphic epiphytes (always high LMA) are significantly more fertile for lower photosynthesis. The role of LMA in framing the rules of competition between stomata and sporangia in monomorphic ferns provides a template for how photosynthesis may directly or indirectly influence reproductive strategies (and vice versa) in all land plants.

Download Full-text

Pengaruh Pupuk Majemuk NPKS dan NPK terhadap Pertumbuhan dan Hasil Padi Sawah pada Inceptisol

Jurnal Penelitian Pertanian Tanaman Pangan ◽

10.21082/jpptp.v34n3.2015.p175-185 ◽

2016 ◽

Vol 34 (3) ◽

pp. 175

Author(s):

Wiwik Hartatik ◽

Ladiyani Retno Widowati

Keyword(s):

Nutrient Uptake ◽

Block Design ◽

Chemical Properties ◽

Dry Weight ◽

Grain Weight ◽

Production Performance ◽

Growth And Yield ◽

Fertilizer Treatment ◽

Optimum Rate ◽

Compound Fertilizer

<p>Rate of NPK fertilization on rice using NPK compound fertilizer needs to consider soil nutrient status and plant nutrient requirement. The research was aimed to determine the optimum rate of compound fertilizer and the effect of enriched S nutrient of NPKS compound (15-15-15-5S) and NPK compound fertilizer (15-15-15) on the growth and yield of rice. The experiments were conducted at two sites in Galuga, Ciampea Bogor, West Java from April to September 2013, using randomised complete block design with 3 replications. Experiment at site I consisted of 9 treatments: six levels of fertilizers NPKS i.e. 0; 150; 300; 450; 600; and 750 kg/ha, standard fertilizer, NPK compound fertilizer equivalent to standard, and standard fertilizer plus S. Rate of urea, SP-36, and KCl for standard fertilizer treatment was respectively 250, 75, and 50 kg/ha. At site II the treatments consisted of 6 levels of NPK compound fertilizer i.e. 0; 150; 300; 450; 600; and 750 kg/ha and the standard fertilizer with rate of 250 kg/ha of urea, 50 kg/ha SP-36, and 75 kg/ha KCl. Plot size was 4 m x 5 m planted with Ciherang variety. Data collection included chemical properties of soil before and after the experiment, plant height, number of tillers, straw weight, and dry grain weight and the nutrient uptake. The effectiveness of fertilizer was calculated by RAE (Relative Agronomic Effectiveness). Results showed that fertilizer NPKS (15-15-15-5S) at 600 kg/ha effectively increased dry grain weight from 3.63 t/ha to 4.67 t/ha, but was not significantly different from a standard fertilizer treatment. It increased dry grain weight by 29% compared to control. NPK fertilizer (15-15-15) effectively promoted growth and dry grain weight equivalent to standard fertilizer at rate of 300-750 kgha. The optimum rate of NPK compound fertilizer (15-15-15) was 440 kg/ha as was shown with the production performance of 4.12 t/ha with RAE by 58%. NPKS compound fertilizer with rate of 750 kg/ha showed the highest uptake of N, P, and K nutrients and significantly increased the available P in the soil. Whereas NPK compound fertilizer with a rate of 600 kg/ha indicated the highest P nutrient uptake. Fertilizer enrichment with sulfur on NPKS fertilizer (15-15-15-5S) did not significant affect on grain dry weight.</p>

Download Full-text

Silicon Improves the Production of High Antioxidant or Structural Phenolic Compounds in Barley Cultivars under Aluminum Stress

Agronomy ◽

10.3390/agronomy9070388 ◽

2019 ◽

Vol 9 (7) ◽

pp. 388 ◽

Cited By ~ 5

Author(s):

Isis Vega ◽

Miroslav Nikolic ◽

Sofía Pontigo ◽

Karina Godoy ◽

María de La Luz Mora ◽

...

Keyword(s):

Phenolic Compounds ◽

Radical Scavenging ◽

Al Toxicity ◽

Growth And Yield ◽

Limiting Factors ◽

Al Tolerance ◽

Short Term ◽

Barley Cultivars ◽

Short Term Exposure ◽

The Impact

Aluminum (Al) toxicity is one of the main growth and yield limiting factors for barley grown on acid soils. Silicon (Si) ameliorates Al toxicity as well as it promotes the phenolic compounds production that have antioxidant or structural role. We evaluated the time-dependent kinetics of Al and Si uptake and the impact of Si on the production of antioxidant- or structural- phenols in barley cultivars at the short-term. Two barley cultivars with contrasting Al tolerance (Hordeum vulgare ‘Sebastian’, Al tolerant; and H. vulgare ‘Scarlett’, Al sensitive), exposed to either −Al (0 mM) or +Al (0.2 mM) nutrient solutions without Si (−Si) or with 2 mM (+Si) were cultured for 48 h. Aluminum and Si concentration decreased in plants at all harvest times when Al and Si were simultaneously supplied; this effect was more noticeable in ‘Scarlett’. Nevertheless, Si influenced the antioxidant system of barley irrespective of the Al tolerance of the cultivar, decreasing oxidative damage and enhancing radical scavenging activity, the production of phenolic compounds, and lignin accumulation in barley with short-term exposure to Al.

Download Full-text

Quackgrass (Agropyron repens) Interference on Corn (Zea mays)

Weed Science ◽

10.1017/s0043174500058860 ◽

1984 ◽

Vol 32 (2) ◽

pp. 226-234 ◽

Cited By ~ 39

Author(s):

Frank L. Young ◽

Donald L. Wyse ◽

Robert J. Jones

Keyword(s):

Zea Mays ◽

Soil Moisture ◽

Leaf Tissue ◽

Nutrient Status ◽

Growing Season ◽

Field Studies ◽

Growth And Yield ◽

Limiting Factors ◽

Corn Yield ◽

Agropyron Repens

Field studies were conducted to evaluate the effect of quackgrass [Agropyron repens(L.) Beauv. ♯ AGRRE] density and soil moisture on corn (Zea maysL.) growth and yield. Quackgrass densities ranging from 65 to 390 shoots/m2reduced corn yield 12 to 16%. A quackgrass density of 745 shoots/m2reduced corn yields an average of 37% and significantly reduced corn height, ear length, ear-fill length, kernels/row, rows/ear, and seed weight. In the soil moisture study, quackgrass was shorter than corn throughout the growing season, and analyses of corn leaf tissue indicated that quackgrass did not interfere with the nutrient status of the corn. In 1979, soil moisture was not limiting and corn yields were similar in all treatments regardless of irrigation or the presence of quackgrass. In 1980, soil moisture was limited and irrigation increased the yield of quackgrass-free corn. Irrigation also increased the yield of quackgrass-infested corn to a level similar to irrigated corn. When light and nutrients are not limiting factors, an adequate supply of soil moisture can eliminate the effects of quackgrass interference on the growth, development, and yield of corn.

Download Full-text

Seed Coating with Arbuscular Mycorrhizal Fungi for Improved Field Production of Chickpea

Agronomy ◽

10.3390/agronomy9080471 ◽

2019 ◽

Vol 9 (8) ◽

pp. 471 ◽

Cited By ~ 4

Author(s):

Inês Rocha ◽

Isabel Duarte ◽

Ying Ma ◽

Pablo Souza-Alonso ◽

Aleš Látr ◽

...

Keyword(s):

Arbuscular Mycorrhizal ◽

Field Conditions ◽

Growth And Yield ◽

Seed Coating ◽

Agricultural Practice ◽

Agricultural Crops ◽

Field Inoculation ◽

Inoculation Methods ◽

Fungal Isolates ◽

The Impact

Although arbuscular mycorrhizal (AM) fungi are known to promote growth and yield of agricultural crops, inoculation methods for effective scaling up from greenhouse to the field are still underexplored. The application of single or mixed beneficial AM fungal isolates is hindered by the lack of experimental reproducibility of findings at different scales and the cost-effectivity of inoculation methods. Seed coating has been considered a feasible delivery system of AM fungal inocula for agricultural crops. In this study, the impact of single and multiple AM fungal isolates applied via seed coating on chickpea productivity was evaluated under greenhouse and field conditions. Overall, plants inoculated with multiple AM fungal isolates had better performance than those inoculated with single AM isolate under greenhouse and field conditions. While plants in greenhouse displayed higher shoot dry weight (14%) and seed individual weight (21%), in field, inoculation with multiple AM isolates increased pod (160%), and seed (148%) numbers, and grain yield (140%). Under field conditions, mycorrhizal root colonization was significantly higher in chickpea plants inoculated with multiple AM fungal isolates compared to other treatments. These findings highlight the potential of field-inoculation with multiple AM fungal isolates via seed coating as a sustainable agricultural practice for chickpea production.

Download Full-text

Growth Response of Seedlings of Four Robusta Coffee (Coffea canephora Pierre. Ex. A. Froehner) Clones to Drought Stress

Pelita Perkebunan (a Coffee and Cocoa Research Journal) ◽

10.22302/iccri.jur.pelitaperkebunan.v35i1.344 ◽

2019 ◽

Vol 35 (1) ◽

pp. 1-11

Author(s):

Novie Pranata Erdiansyah ◽

Ade Wachjar ◽

Eko Sulistyono ◽

Supijatno Supijatno

Keyword(s):

Drought Stress ◽

Block Design ◽

Free Water ◽

Coffea Canephora ◽

Growth And Yield ◽

Limiting Factors ◽

Coffee Plantations ◽

Robusta Coffee ◽

Randomized Block Design ◽

Two Factors

Drought is one of the limiting factors for the growth and yield of coffee plants. Drought due to long dry season has caused many losses for coffee plantations. This study aimed to evaluate the response of four Robusta coffee clones to drought stress at seedling stage and determine the best clone with high tolerance to drought. The study was conducted in Indonesian Coffee and Cocoa Reseach Institute (ICCRI) Jember, East Java in November 2018–Mei 2019. The experimental design used a Randomized Block Design (RCBD) with two factors. The first factor has consisted of five levels drought through providing volume watering based coefficient and evaporation value of free water surface (Eo), namely: 0.5 Eo; 1.0 Eo; 1.5 Eo; 2.0 Eo; 2.5 Eo (control). The second factor has consisted of four Robusta coffee clones, namely: BP 409 (drought tolerant clone); BP 308; BP 939 and BP 358 (vulnerable to drought stres). The result showed that reduction in the volume of watering from 2.5 Eo until 0.5 Eo causes drought, reduce coffee growth linearly. Clone BP 409 and BP 939 had better tolerance of drought stress compared with BP 308 and BP 358. The anatomical adaptation of leaves of BP 409 to drought stress was by thickening of wax layer and palisade tissue. BP 939 thickened its leaves due to drought stress as a mechanism of adaptation to such condition.

Download Full-text

UPAYA PENINGKATAN HASIL MENTIMUN SECARA ORGANIK DENGAN SISTEM TASALAMPOT

JURNAL AGROTEKNOLOGI ◽

10.24014/ja.v6i1.1372 ◽

2016 ◽

Vol 6 (1) ◽

pp. 17

Author(s):

INDAH PERMANASARI ◽

AULIA RANI ANNISAVA

Keyword(s):

Oil Palm ◽

Block Design ◽

Organic Fertilizer ◽

Poultry Manure ◽

Dry Weight ◽

Growth And Yield ◽

Agricultural Practice ◽

Randomized Block Design ◽

Crop Density ◽

Cucumber Yield

Utilization of organic material in crop farming is one of the methods to exploit the local wisdom in agricultural practice. The research was conducted from June to September 2012 in the research farm, State Islamic University of Sultan Syarif Kasim Riau. The objective of the research was to investigate the effects of organic materials and crop density ? in growth and yield on cucumber. Randomized block design with 2 factors and 4 replications was employed in this study. The first factor consists of three levels organic fertilizer treatments i.e. no fertilizer, poultry manure, and compost of oil palm empty bunch. Second factor comprises of three levels of crop density i.e. 1, 2, and 3 plants per pot).. The results showed that there was significant increase on growth and yield on cucumber with poultry manure treatment compare to that of with compost of oil palm empty bunch. Increasing crop density ? improves the number and weight of cucumber yield per pot, even though, some parameters, i.e. number of leaves, stem diameter, crop dry weight, productive number of branches, cucumber size and cucumber weight per plant were significantly decreased.

Download Full-text

Estimating Yield Components, Limiting Factors, and Yield Gaps of Enset in Ethiopia Using Easily Measurable Above-Ground Plant Traits

Sustainability ◽

10.3390/su132313255 ◽

2021 ◽

Vol 13 (23) ◽

pp. 13255

Author(s):

Zerihun Yemataw ◽

Alemar Said ◽

Tesfaye Dejene ◽

Walter Ocimati ◽

David Amwonya ◽

...

Keyword(s):

Plant Traits ◽

Strong Association ◽

Yield Component ◽

Growth And Yield ◽

Limiting Factors ◽

Yield Traits ◽

Yield Attributes ◽

Allometric Models ◽

Fiber Yield ◽

Yield Gaps

The quantification of yield for different enset products has mainly been based on farmers’ estimates, which are often inaccurate. Several allometric models have been developed to overcome this challenge. Building on past work, the current study developed allometric models for enset fiber, kocho, and bula yield estimation. Enset yield limiting factors and associated yield gaps were also determined. In this study, above-ground growth and yield (kocho, bula, and fiber) traits of five-year-old plants of two widely grown enset landraces, ‘Unjame’ and ‘Siskela’, were assessed in farmers’ fields at three contrasting altitude sites. Except for bula, a minor yield component, correlation, and PCA analysis showed strong association between the above-ground and yield traits. Allometric equations based on the above-ground traits significantly (R2 = 25 to 68%) explained the variation in the yield traits. This study, for the first time, generated allometric models that can reliably estimate enset fiber yield. Leaf length, petiole length, and plant height are especially good for estimating fiber and kocho yields. The performance of models for bula were poor possibly due to the very low bula yields per plant. Soil chemical characteristics differently influenced enset yield attributes. For example, improving K supply can potentially enhance fiber yield. Higher yield gaps were observed for bula, with P accounting for the highest yield gaps across yield traits. Through careful targeting, the different yield attributes can thus be enhanced. This and previous studies clearly show that non-destructive enset plant assessments can provide solid information for quick and easy yield assessments for various traits during e.g., agronomic, germplasm evaluation, soil fertility enhancement, and intercropping trials.

Download Full-text