Effect of fertigation with potassium and nitrogen on gas exchange and biomass accumulation in eggplant1

Abstract

Adequate crop fertilization is one of the challenges for agriculture. Measuring gas exchange and biomass accumulation may be used to adjust crop management. The effect of fertigation with potassium (0 kg ha-1, 54 kg ha-1, 108 kg ha-1 and 216 kg ha-1) and nitrogen (0 kg ha-1, 67 kg ha-1, 134 kg ha-1 and 268 kg ha-1) on gas exchange and biomass accumulation in eggplant was assessed under greenhouse conditions. The net photosynthesis, stomatal conductance, transpiration, internal CO2 concentration, instantaneous carboxylation efficiency, water-use efficiency and total dry weight were evaluated. With the exception of K for water-use efficiency and N for internal CO2 concentration, all the other gas exchange parameters were significantly affected by the K and N doses. There was an interaction between N and K doses for net photosynthesis, stomatal conductance, transpiration and instantaneous carboxylation efficiency. The highest values for net photosynthesis, stomatal conductance, transpiration rate, carboxylation instantaneous efficiency and total dry weight were found in the range of 125-185 kg ha-1 of K and 215-268 kg ha-1 of N.

Enhancing Sustainability in Potato Crop Production: Mitigating Greenhouse Gas Emissions and Nitrate Accumulation in Potato Tubers through Optimized Nitrogen Fertilization

“…N application rates and sources promoted diverse effects on gas exchange parameters [29,30]. The application of rates exceeding 110 and 91 kg N ha −1 for stomatal conductance and net photosynthetic rate, respectively, coupled with lower yields, indicates that an increase in N supply beyond the optimal rate disrupts physiological mechanisms, manifesting in diminished tuber biomass production.…”

“…Given that ammonium nitrate already contains N in the form of NO 3 − , it offers a more readily available source of nitrate for plants. Consequently, when fertilized with ammonium nitrate, plants can absorb nitrate more quickly, resulting in greater nitrate accumulation in plant tissues compared to urea fertilization [29].…”

Growth and accumulation of macronutrients in arugula

“…The seedlings remained in a protected environment, and at 21 days, counted from sowing, were transplanted in the definitive beds, using the spacing of 0.25 x 0.25 meters. The treatments consisted of different collection times (7,14,21,28, 35 e 42 days after transplanting the seedlings), distributed based on the arugula cultivation cycle.…”

“…A nutrient absorption march is a tool adopted in crops for informing in the form of response curves as a function of plant age, periods of higher nutrient absorption, as well as the largest quantities, indicating the times of greatest nutritional demand, thus constituting a tool of great importance for the management and fertilization of crops [32]. Some studies on growth and accumulation of nutrients in vegetables have been carried out on tomatoes [5], beet [25], eggplant [28], and lettuce [26]. Regarding the arugula, there is little information in the literature about the higher demand for nutrients required by the crop, as well as the total amount extracted of nutrients requiring research on the accumulation of nutrients, because this technique related to the productivity gain of the culture is understudiedin the country.…”