Role of Combined Inoculation with Arbuscular Mycorrhizal Fungi, as a Sustainable Tool, for Stimulating the Growth, Physiological Processes, and Flowering Performance of Lavender

Arbuscular mycorrhizal fungi (AMF) are essential soil microorganisms for terrestrial ecosystems and form beneficial symbioses with the root systems of most agricultural plants. The purpose of this paper was to examine the effect of the community of six AMF on the growth, physiological response, and flowering performance in organic potted lavender culture. The mixture of AMF containing Rhizophagus irregularis, Claroideoglomus claroideum, Funneliformis mosseae, Funneliformis geosporum, Claroideoglomus etunicatum, and Glomus microaggregatum was added in a pot with peat, volcanic rock, and coconut bark. We analyzed the fresh shoot biomass, root biomass, total plant biomass, leaf area, flowering performance, photosynthesis rate, and photosynthetic pigment content. Pearson’s correlation coefficient was performed to get a better understanding of the relationships between the studied variables. The total plant biomass was more pronounced in plants with AMF-S20g (212.01 g plant−1) and AMF-S30g (220.25 g plant−1) than with AMF-S10g (201.96 g plant−1) or in untreated plants (180.87 g plant−1). A statistically significant increase for Chl a, Chl b, and Car was found for AMF-S20g and AMF-S30. Our findings suggest that the AMF mixture application in a growing substrate with peat, coconut bark, and volcanic rock improved plant growth, physiological processes, and ornamental value in mycorrhizal lavender plants. This environmentally friendly agricultural practice could be used for the sustainable production of lavender.

Influence of Copper Pollution of Haplic Calcic Chernozem With Various Contents of Sand Fractions on Morphobiometric Indicators of Spring Barley

The growth and development of plants is one of the criteria for assessing the degree of soil pollution with heavy metals. Morphological and anatomical changes in test plants affected by pollutants, such as growth retardation, shoot bending, and decreased root length and mass, indicate the worsening of environmental conditions. The effect of various ratios of soil and sand polluted with copper (Cu) on morphobiometric parameters of spring barley (Hordeum sativum distichum), Ratnik variety, was studied in a model vegetative experiment. Haplic calcic chernozem was used as a substrate with different ratios of soil/sand. It was determined that an addition of sand into the soil in the amounts of 25%, 50% and 75% of soil mass resulted in the alteration of the physical properties of the chernozem, which was reflected in the morphometric parameters of the plants. The most notable changes in the parameters were observed after pollution of soil-sand substrates with Cu(CH3COO)2 in the amounts of 250 mg/kg, 500 mg/kg, 1000 mg/kg and 2000 mg/kg. The maximum growth and development retardation of the barley plants was found at the maximum content of sand and the maximum concentration of Cu. The pollutant reduced the root length and, to a lesser degree, the height of the aboveground components of the plant, which as a result, decreased the total plant biomass. Keywords: trace elements, soil, agricultural crops, particle size distribution

Cause of Death: Phytophthora or Flood? Effects of Waterlogging on Phytophthora medicaginis and Resistance of Chickpea (Cicer arietinum)

Chickpea production in Australia is constrained by both waterlogging and the root disease Phytophthora root rot (PRR). Soil saturation is an important pre-condition for significant disease development for many soil-borne Phytophthora spp. In wet years, water can pool in low lying areas within a field, resulting in waterlogging, which, in the presence of PRR, can result in a significant yield loss for Australian chickpea varieties. In these circumstances, the specific cause of death is often difficult to discern, as the damage is rapid and the spread of PRR can be explosive in nature. The present study describes the impact of soil waterlogging on oxygen availability and the ability of P. medicaginis to infect chickpea plants. Late waterlogging in combination with PRR reduced the total plant biomass by an average of 94%; however, waterlogging alone accounted for 88% of this loss across three reference genotypes. Additional experiments found that under hypoxic conditions associated with waterlogging, P. medicaganis did not proliferate as determined by zoospore counts and DNA detection using qPCR. Consequently, minimizing waterlogging damage through breeding and agronomic practices should be a key priority for integrated disease management, as waterlogging alone results in plant stunting, yield loss and a reduced resistance to PRR.

Differences in morphological and physiological features of citrus seedlings are related to Mg transport from the parent to branch organs

Background In this study, we aimed to test the hypothesis that magnesium (Mg) remobilization in citrus plants is regulated by Mg supply and contributes to differences in the growth of the parent and branch organs. Citrus seedlings were grown in sand under Mg deficient (0 mmol Mg2+ L−1, -Mg) and Mg sufficient (2 mmol Mg2+ L−1, + Mg) conditions. The effects on biomass, Mg uptake and transport, gas exchange and chlorophyll fluorescence, as well as related morphological and physiological parameters were evaluated in different organs. Results Mg deficiency significantly decreased plant biomass, with a decrease in total plant biomass of 39.6%, and a greater than twofold decrease in the branch organs compared with that of the parent organs. Reduced photosynthesis capacity was caused by a decreased in pigment levels and photosynthetic electron transport chain disruption, thus affecting non-structural carbohydrate accumulation and plant growth. However, the adaptive responses of branch leaves to Mg deficiency were greater than those in parent leaves. Mg deficiency inhibited plant Mg uptake but enhanced Mg remobilization from parent to branch organs, thus changing related growth variables and physiological parameters, including protein synthesis and antioxidant enzyme activity. Moreover, in the principal components analysis, these variations were highly clustered in both the upper and lower parent leaves, but highly separated in branch leaves under the different Mg conditions. Conclusions Mg deficiency inhibits the growth of the parent and branch organs of citrus plants, with high Mg mobility contributing to differences in physiological metabolism. These findings suggest that Mg management should be optimized for sustainable citrus production.

Nitrogen Uptake from Different Sources by Soybean Grown at Different Sowing Densities

The objective of the research reported here was to determine the amount of nitrogen fixed from the atmosphere and taken up from mineral fertilizer and soil reserves by soybean cv. Abelina grown at three densities (per 1 m2) under central European conditions. Moreover, an attempt was made to determine what amount of nitrogen taken up from the individual sources was removed from the field with seed yield and was introduced to the soil with post-harvest residues and that will be the source of this macronutrient for the following plants. The following densities were used: A1–50 seeds, A2—70 seeds and A3—90 seeds per 1 m2. The share of nitrogen derived from the atmosphere, soil reserves and mineral fertilizer and taken up by the total plant biomass was 46.28, 45.52 and 8.2%, respectively. The whole biomass accumulated 58.51, 52.85 and 9.71 kg N∙ha−1 from the respective sources. An average of 95.24 kg N∙ha−1 was removed from the field with seeds, it being 46.17, 42.20 and 6.68 kg N∙ha−1 for an uptake from the atmosphere, soil reserves and mineral fertilizer, respectively. An incorporation into soil of residues and roots provided over 25.82 kg N∙kg−1 associated with all the sources.

The Role of Trichoderma Species in Plants Response to Salt Stress

Soil salinity is a pending threat to global agricultural sustainability and food security. The natural means of alleviating this stress have become the major concern as to which methods, mechanisms, and organisms to be used. Soil-borne fungi Trichoderma has proven to alleviate salinity stress in plants. This review aimed to shed light on the roles and mechanisms of some species of Trichoderma in response to salt stress and other merits to plant growth and development. Detailed of this research reviewed the level of growth promotion induced by Trichoderma species with an estimated increase of 200% of total plant biomass compared with control plants from literature. The defined mechanisms of Trichoderma in combating salinity stress in plants are; formation of ion channels in host plants, activation of ion exchange (K+/N+), increase Reactive Oxygen Species (ROS) scavenging enzymes, antioxidants, and genes, production of phytohormones and their signal pathways, stimulates root formation and developments, regulate stomata conductance through the increment of carotenoids in host plants which corresponds to the functions of the photosystems.

ESTIMATION OF BIOMASS POTENTIAL IN THE HAU MY BAC B COMMUNE, CAI BE DISTRICT, TIEN GIANG PROVINCE

All field survey data is analyzed for a material flow considering biomass use in the Hau My Bac B Commune, Cai Be District, Tien Giang Province. The statistical results show that the amount of biomass is significantly produced by three sources: crop residues, livestock waste, and domestic waste from which the percentages of biomass were ultilized by 17%, 39%, and 5%, respectively. The amount of crop residues is also estimated at the highest volume in total plant biomass where straw with the high calorie value and low-cost should be utilized as bioenergy.

Strength and Size of Phosphorus-Rich Patches Determine the Foraging Strategy of Neyraudia reynaudiana

Background: Under natural conditions, soil nutrients are heterogeneously distributed, and plants have developed adaptation strategies to efficiently forage patchily distributed nutrient. Most previous studies examined either patch strength or patch size separately and focused mainly on root morphological plasticity (increased root proliferation in nutrient-rich patch), thus the effects of both patch strength and size on morphological and physiological plasticity are not well understood. In this study, we examined the foraging strategy of Neyraudia reynaudiana (Kunth) Keng ex Hithc, a pioneer grass colonizing degraded sites, with respect to patch strength and size in heterogeneously distributed phosphorus (P), and how foraging patchily distributed P affects total plant biomass production. Plants were grown in sand-culture pots divided into ½, ¼, 1/6 compartments and full size and supplied with 0 + 0/30, 0 + 7.5/30 and 7.5 + 0/30 mg P/kg dry soil as KH2PO4 or 0 + 15/15, 0 + 18.5/ 18.5, 7.5 + 15/15 mg kg−1 in the homogenous treatment. The first amount was the P concentration in the central region, and that the second amount was the P concentration in the outer parts of the pot.Results: After 3 months of growth under experimental conditions, significantly (p < 0.05) high root elongation, root surface area, root volume and average root diameter was observed in large patches with high patch strength. Roots absorbed significantly more P in P-replete than P-deficient patches. Whole plant biomass production was significantly higher in larger patches with high patch strength than small patches and homogeneous P distribution.Conclusion: The result demonstrates that root morphological and physiological plasticity are important adaptive strategies for foraging patchily distributed P and the former is largely determined by patch strength and size. The results also establish that foraging patchily distributed P resulted in increased total plant biomass production compared to homogeneous P distribution.

Strength and size of phosphorus-rich patches determine the foraging strategy of Neyraudia reynaudiana

Background Under natural conditions, soil nutrients are heterogeneously distributed, and plants have developed adaptation strategies to efficiently forage patchily distributed nutrient. Most previous studies examined either patch strength or patch size separately and focused mainly on root morphological plasticity (increased root proliferation in nutrient-rich patch), thus the effects of both patch strength and size on morphological and physiological plasticity are not well understood. In this study, we examined the foraging strategy of Neyraudia reynaudiana (Kunth) Keng ex Hithc, a pioneer grass colonizing degraded sites, with respect to patch strength and size in heterogeneously distributed phosphorus (P), and how foraging patchily distributed P affects total plant biomass production. Plants were grown in sand-culture pots divided into ½, ¼, 1/6 compartments and full size and supplied with 0 + 0/30, 0 + 7.5/30 and 7.5 + 0/30 mg P/kg dry soil as KH2PO4 or 0 + 15/15, 0 + 18.5/ 18.5, 7.5 + 15/15 mg kg − 1 in the homogenous treatment. The first amount was the P concentration in the central region, and that the second amount was the P concentration in the outer parts of the pot. Results After 3 months of growth under experimental conditions, significantly (p < 0.05) high root elongation, root surface area, root volume and average root diameter was observed in large patches with high patch strength. Roots absorbed significantly more P in P-replete than P-deficient patches. Whole plant biomass production was significantly higher in larger patches with high patch strength than small patches and homogeneous P distribution. Conclusion The result demonstrates that root morphological and physiological plasticity are important adaptive strategies for foraging patchily distributed P and the former is largely determined by patch strength and size. The results also establish that foraging patchily distributed P resulted in increased total plant biomass production compared to homogeneous P distribution.

Strength and Size of Phosphorus-Rich Patches Determine the Foraging Strategy of Neyraudia reynaudiana

Background: Under natural conditions, soil nutrients are heterogeneously distributed, and plants have developed adaptation strategies to efficiently forage patchily distributed nutrient. Most previous studies examined either patch strength or patch size separately and focused mainly on root morphological plasticity (increased root proliferation in nutrient-rich patch), thus the effects of both patch strength and size on morphological and physiological plasticity are not well understood. In this study, we examined the foraging strategy of Neyraudia reynaudiana (Kunth) Keng ex Hithc, a pioneer grass colonizing degraded sites, with respect to patch strength and size in heterogeneously distributed phosphorus (P), and how foraging patchily distributed P affects total plant biomass production. Plants were grown in sand-culture pots divided into ½, ¼, 1/6 compartments and full size and supplied with 0 + 0/30, 0 + 7.5/30 and 7.5 + 0/30 mg P/kg dry soil as KH2PO4 or 0 + 15/15, 0 + 18.5/ 18.5, 7.5 + 15/15 mg kg−1 in the homogenous treatment. The first amount was the P concentration in the central region, and that the second amount was the P concentration in the outer parts of the pot. Results: After 3 months of growth under experimental conditions, significantly (p < 0.05) high root elongation, root surface area, root volume and average root diameter was observed in large patches with high patch strength. Roots absorbed significantly more P in P-replete than P-deficient patches. Whole plant biomass production was significantly higher in larger patches with high patch strength than small patches and homogeneous P distribution. Conclusion: The result demonstrates that root morphological and physiological plasticity are important adaptive strategies for foraging patchily distributed P and the former is largely determined by patch strength and size. The results also establish that foraging patchily distributed P resulted in increased total plant biomass production compared to homogeneous P distribution.