N. Pascual-Seva

Growth and nutrient absorption in chufa (Cyperus esculentus L. var. sativus Boeck.) in soilless culture

Summary The efficiency of fertilisation in agriculture is often low and, provided one knows the nutrient uptake rate, the efficiency can be improved by synchronising nutrient supply with nutrient demand. Growth, the time-course of nutrient accumulation and its partitioning between different organs in chufa (Cyperus esculentus L. var. sativus Boeck.), an under-exploited cultivated plant, were examined. The study was conducted in soilless, open-field conditions, at a planting density equivalent to 55,500 plants ha−1 in three consecutive seasons. Plants were sampled, fractionated into leaves, roots, and tubers, then dried and weighed. Their macronutrient contents were analysed each fortnight. On average, the yield was 5.0 kg fresh weight of tuber m−2. Growth of whole plants, until 90 d after planting, obeyed an exponential function of time. The relative growth rate (RGR) for this period was therefore determined. The highest N and K concentrations were recorded in leaves, and the highest P, Ca, and Mg concentrations were found in roots. The highest accumulations of N and P were found in tubers, and of K and Ca in leaves. Nitrogen had the highest nutrient accumulation (58.3 g m−2) as well as the highest specific uptake rate.

Saving Water in Chufa Cultivation by Using Flat Raised Beds and Drip Irrigation

AbstractChufa, also known as tigernut, is a typical crop in Valencia, Spain, where it is cultivated in ridges with furrow irrigation. This paper examines the effects of the planting strategy (PS) and irrigation system (IS) on yield and irrigation water use efficiency (IWUE) on the basis of the results from a two-year study. The authors analyzed three PS, ridges with a plant row (R) and flat raised beds containing two (B2) or three (B3) plant rows and compared two IS, furrow (FI) and drip irrigation (DI). Irrigation was based on the volumetric soil water content (VSWC), continuously monitored with capacitance sensors. Each irrigation event started when the VSWC in R dropped to 60 or 80% of the field capacity in FI or DI, respectively. Beds and ridges were irrigated simultaneously and for the same duration. There were differences among IS and PS, with DI and B2 obtaining the highest yield. On average, DI produced higher IWUE values than FI; the highest IWUE was obtained in R for DI, and the lowest IWUE was ...

Growth and nutrient absorption of Cape Gooseberry (Physalis Peruviana L.) in soilless culture

Cape gooseberry (Physalis peruviana L.) is a solanaceous plant. The growth and time-course of nutrient accumulation of the plant and its partitioning between roots, stems, leaves, and fruits were examined. The study was conducted analyzing two nutrient solutions in soilless culture under greenhouse conditions during two consecutive seasons. The macronutrient contents were analyzed. On average, the yield was 8.9 t·ha−1. Growth of the plant until 90 d after transplanting obeys an exponential function of time and the relative growth rate for this period was determined. Nitrogen (N) was the element that showed the highest concentration, corresponding to leaves (4.67%), followed by potassium (K) in stems (4.46%). The highest accumulations of N, phosphorous (P), calcium (Ca), and magnesium (Mg) were found in leaves and of K in the stems. Potassium showed the highest nutrient accumulation (29 g·plant−1) and the highest specific uptake rate.

Influence of Growing Media on Physiological Disorders Incidence in Oriental Radishes.

Some cultivar radishes of ‘Daikon’ or oriental radish (Raphanus sativus L. var. longipinnatus L.H. Bailey) have largely replaced in Spain the cultivation of turnips (Brassica napus L.). Market acceptance of these taproots can be affected by the incidence of various physiological disorders, such as the cracking, hollowness, malformation and the emission of secondary roots. We used two Korean cultivars, ‘Spring Favor’ and ‘Spring White’ in greenhouse cultivation in two production cycles, autumn-winter and spring season, in containers of 25 L filled with three substrates, perlite B12, coir dust and sand. In these experiments, designed according to a factorial program, we tried to establish the influence of cultivars, maturity stages and growing media on the incidence of mentioned physiological disorders, commercial production, taproot shape and size, and leaves dry weight. ‘Spring White’ was more susceptible to cracking and malformation than ‘Spring Favor’ while ‘Spring Favor’ showed a greater susceptibility to hollowness and secondary roots emission, ‘Spring White’ taproots were longer and less wide than ‘Spring Favor’. Over-maturity taproots did not influence on the hollowness and malformation. Among the three used substrates, perlite behaved worse in the incidence of almost all studied physiological disorders, while it seems that sand and coir dust did not adversely affect them. No many significant interactions were detected between cultivars x substrates.