A Comprehensive Look at Nitrogen and Phosphorus Use Efficiency in Saffron (Crocus Sativus L.)

Saffron (Crocus sativus L.) is an annual plant from a biological aspect, but it has a perennial cycle in the field conditions. Cytological impairments such as triploid and self-incompatibility mechanisms are considered as the most important reasons for male-sterility in saffron. Therefore, saffron reproduction is made by meristems tissues and establishment of new daughter corms which are produced by the mother corms. During the growing season, mother corms deteriorate gradually with increasing daughter corms growth. Each daughter corm is considered as a mother corm for replanting in the next growing season. Duo to the life cycle of saffron as a perennial plant in the field conditions, the gradual deterioration of mother corms during the growing season and also the remobilization of nitrogen and phosphorus from aerial part to daughter corms at the end of each growing season, the study of acquisition and use efficiency of nitrogen and phosphorus in saffron is more complicated than other annual or biannual plants. Firstly, the objective of this review article is to describe the nitrogen and phosphorus concentration in aerial parts and daughter corms in saffron. In addition, relevant literature related to the most important strategies for improving nitrogen and phosphorus use efficiency is reviewed. Secondly, the relationship between nitrogen and phosphorus use efficiency in saffron is discussed

Effects of Corm Size, Organic Fertilizers, Fe-EDTA and Zn-EDTA Foliar Application on Nitrogen and Phosphorus Uptake of Saffron (<i>Crocus sativus</i> L.) in a Calcareous Soil under Greenhouse Conditions

A greenhouse research experiment was conducted. The experiment was arranged in factorial layout based on a completely randomized design. The mother corm size (0.1-4 g, 4.1-8 g and 8-12 g), organic fertilizers (cattle manure 15 t ha-1, vermicompost 10 t ha-1,chamomilecompost 10 t ha-1 and control) and micronutrients (Fe-EDTA and Zn-EDTA) in two levels (foliar application and no application) were assigned as the first, second and third experimental factors, respectively. Based on the results, with increasing mother corm size, formation of small corms (0.1-4 g) decreased, whereas the percentage of medium (4.1-8 g) or large size (more than 8 g) corms increased. The highest corm yield was observed when cattle manure was applied. Moreover, foliar application increased daughter corm yield in medium and larger size corms. Phosphorus and nitrogen concentration in daughter corms increased with increasing the size of mother corms. Organic fertilizers significantly increased phosphorus and nitrogen concentration in all size of corms: phosphorus content in large daughter corms increased five times on account of cattle manure application. Proper nutrient management during the first year of saffron propagation could improve corm number than rather corm weight

Effects of Different Water Supply and Corm Planting Density on Crocin, Picrocrocin and Safranal, Nitrogen Uptake and Water Use Efficiency of Saffron Grown in Semi-Arid Region

Saffron’s color, taste and odor result from the chemicals crocin, picrocrocin and safranal, respectively. Hence, in addition to quantitative yield, secondary metabolites content are known as crucial factors for a successful saffron production. Moreover, enhancing resources efficiency, especially water and nitrogen, is becoming increasingly important for agricultural improvement in arid and semi-arid regions. Thus, the effects of irrigation levels and corm planting on crocin, picrocrocin and safranal content, water use efficiency (WUE) as well as nitrogen use efficiency (NUE) of saffron were investigated as a two-year field experiment based on a randomized complete block design arranged in split-plot with three replicates. The irrigation levels (100, 75 and 50% of saffron water requirement) and corm planting pattern (50, 100, 200 and 300 corms m-2) were allocated to main and sub-plots, respectively. Based on the results, crocin and picrocrocin content increased with decreasing irrigation levels. The highest WUES (WUE based on dry stigma yield) was obtained when 50% of saffron water requirement was supplied. However, the lowest WUEC (WUE based on daughter corms yield) and NUEC (NUE based on daughter corms yield) were obtained when 50% of saffron water requirement was applied. Irrespective of irrigation levels, WUES, WUEC and NUEC increased with increasing the planting density. The results demonstrated that although relatively severe water stress increases WUES and secondary metabolites in saffron stigmas, it could decrease WUEC and NUEC through affecting daughter corm growth

Effect of corm planting density, organic and chemical fertilizers on formation and phosphorus uptake of saffron (Crocus sativus L.) replacement corms during phonological stages

Saffron (Crocus sativus L.) propagates by replacement corms producing from the mother corm after flowering during each season. In order to investigate the effect of corm planting density, organic and chemical fertilizers on formation and phosphorus uptake of saffron replacement corms during phonological stages, a field experiment was conducted as factorial layout based on randomized complete block design with three replications, at Faculty of Agriculture, Ferdowsi University of Mashhad, Iran, during 2013 and 2014 growing seasons. The experimental treatments were all combination of different levels of planting density (25, 50, 75 and 100 corms per m2) and fertilizer sources (manure 25 t. ha-1, chemical fertilizer (N 150 kg ha-1 + P 75 kg ha-1) and control). Due to different sampling dates of replacement corms during phonological stages (21 November, 21 December, 20 January, 20 April and 21 May, respectively), the experimental data were analyzed as factorial - split in time based on a randomized complete block design. Based on results, the highest number of replacement corms lower than 4 g (5.8 corms per plant) were observed in fifth sampling stage and then decreased. In all levels of planting density (25 to 100 corms per m2), the effects of manure on increasing the number, weight and phosphorus content of replacement corms in range of 4.1 to 8 and 8.1 to 12 g per plant were significantly higher than chemical fertilizer. In fifth sampling stage, by applying the manure, the weight and phosphorus content of replacement corms in range of 8.1 to 12 g per plant were significantly increased (approximately twice), as compared to chemical fertilizer. It seems the decrease in saffron yield as result to decreasing the corm planting density can be slightly offset by increasing the percentage of larger corms formation per plant

The effects of mother corm size and type of fertilizer on nitrogen use efficiency in saffron

Mother corm size and nutrient management are the most important factors in relation to nitrogen uptake of saffron (Crocus sativus L.). In order to investigate the effects of mother corms size and type of fertilizer on uptake and use efficiency of nitrogen in Saffron, a field experiment was conducted as factorial layout based on a randomized complete block design with three replications at Faculty of Agriculture, Ferdowsi University of Mashhad, Iran, during the years 2013 and 2014. The mother corm size (4 g and lower (small), 4.1–8 g (medium), 8.1-12 g (relatively large) and over 12 g (large)) and fertilizer sources (cow manure 25 t ha-1, chemical fertilizer (N+P) and control) were the first and second experimental factors, respectively. In both years, the larger mother corms (8.1-12 g and more) significantly resulted in greater nitrogen content (g m-2) of replacement corms and whole plant of saffron. In addition, uptake and use efficiency of nitrogen were significantly increased with increasing mother corms size. In the first and the second years, nitrogen use efficiency in manure treatment was significantly higher than that of chemical fertilizer (by 21 and 61%, respectively)

Effects of Fertilizers and Priming with KH2PO4 Solution on Emergence and Heterotrophic Growth of Black Cumin (Nigella sativa) Seedling

In order to investigate the effects of priming with a KH2Po4 solution on emergence and heterotrophic growth of black cumin (Nigella sativa L.) seedling, a series of experiments were conducted at the Faculty of Agriculture, Ferdowsi University of Mashhad, Iran, in 2013 and 2014. A field experiment was conducted as factorial layout based on a randomized complete block design with four replications. The fertilizer resources (vermicompost (V)+Tiobacilus (T), micronized Sulfur (S)+T, V+S+T and control) and three levels of phosphorus (0, 30 and 60 kg.ha-1) were the first and second experimental factors, respectively. In the second experiment, selected treatments (in which showed emergence below 60% in the previous experiment) and seed priming (no priming, hydro priming and three levels of phosphorus (P)-priming as 100, 300 and 500 mM KH2Po4) were the first and second experimental treatments, respectively. Based on the results, the resources of soil amendment (V+T and V+S+T) significantly increased the emergence percentage of black seed (by 50 and 54%, respectively). In addition, seed reserve depletion percentage, seed reserve utilization efficiency and emergence percentage significantly increased by 300 mM KH2PO4 (by 9, 143 and 29%, respectively). There was a significant positive relationship between the weight of mobilized seed P and the emergence percentage of black seeds (R2= 0.90 **)

Weed Competition Periods Affect Grain Yield and Nutrient Uptake of Black Seed (Nigella Sativa L.)

The combination of the relatively open plant canopy and slow growth, especially at early growth stages, results in lower competitiveness of black seed (Nigella sativa L.) than weeds. Thus, weed interference is known as an important factor affecting black seed yield. Therefore, to determine the critical period of weed control and its effects on nutrients uptake of black seed field experiments were conducted in 2011 and 2012. Two quantitative series of weed removal treatments including weed-infested and weed-free treatments were implemented from black seed emergence to maturity harvest. To determine critical period of weed control, plots were weed-infested or weed-free for 0, 14, 28, 42, 56, 70 days after emergence, in weed-infested and weed-free treatments, respectively. The results revealed that N, P and K contents in weed tissues significantly increased with increasing weed-infested periods during both years of the experiment. The reduction in grain and oil yield due to longer periods of weed-infested conditions or shorter periods of weed-free conditions were accompanied by simultaneous reduction of N, P and K uptake in black seed grains and tissues. Overall, N, P and K contents in weed tissue were found to be 1.8 to 2 times higher than that of black seed. It was concluded that 58 or 49 days weed-free periods are required to avoid yield loss (above 5% or 10%) in black seed

The subsurface application of pistachio waste compost and foliar spraying of organic matter can induce the flower yield and the quality of saffron (Crocus sativus L.) corms affected by restricted nutrient conditions

Correct use of organic waste in the form of composting can play a constructive role in reducing environmental pollution and increasing saffron sustainable production. Recently, pistachio waste compost has been considered as a soil conditioner, especially in arid and semi-arid areas. Along with improving the organic structure, foliar application of amino acids through the recommendation of reputable companies is another sustainable solution that can further strengthen the relationship between trade and agriculture. The current study was conducted in Anbari Agricultural Seeds Company, Mashhad, Iran during 2019–2021. The experiment was performed with three replicates based on a randomized complete block design arranged in factorial-split including 12 main plots [Organic fertilizer (control, pistachio compost (P), wheat straw (W), cow manure (M), P + W, and P + M) × Foliar spraying (control and 2 L. ha−1 DRIN: a commercial organic compound)] and 2 sub-plots (first and second sampling). The minimum number of saffron flowers and stigma weight were observed under no-organic fertilizer; while all organic sources led to increase these traits. The values increased by 27% and 31%, respectively, resulting pistachio compost compared to control treatment. Applying organic sources resulted in a higher crocin and safranal. At the same time, foliar spraying had a significant effect in increasing crocin and safranal concentrations. Organic fertilizers and foliar spraying caused a significant effect in terms of N, P, and K concentration in daughter corms. when control treatment was considered, foliar spraying increased sucrose by 24% compared to non-spraying. Furthermore, sucrose content was recorded to be improved following all organic amendments. Similar responses were observed regarding arginine, glutamic acid, alanine, and aspartic acid. Overall, applying pistachio compost concurrent with spraying of DRIN is recommended for saffron sustainable production, especially under nutrient-restricted conditions