Daughter Corms Research Articles

Study of the Effect of Pretreatment of Corms by Different Concentrations of Gibberellic Acid and at Different Periods on the Growth, Flowering, and Quality of Saffron in Eastern Morocco

The present study was conducted to evaluate the influence of gibberellic acid (25, 50, 100, and 200 ppm) applied on saffron corms previously harvested during different periods (March, June, and before planting) on the growth and the quantitative and qualitative yield of saffron (Crocus sativus L.). The study was carried out in the field during the 2016-2017 and 2017-2018 seasons in the experimental station of the Faculty of Sciences of Oujda (Morocco). The measured parameters correspond, on the one hand, to morphometric measurements and to the determination of the saffron stigma yield and, on the other hand, to the evaluation of the quality of the spice. The results showed that almost all the parameters studied were significantly affected by the factors considered. The treatment of corms just before planting with concentrations of 100 and 200 ppm GA3 showed the highest flower and leaf appearance rate and the highest leaf length and surface area. Moreover, the application of GA3 during the month of March gave the best results in terms of stigmata yield, percentage of large-diameter daughter corms, and the ratio of the number of flowers produced to the total weight of corms. The results of the coefficient of corm propagation revealed that the application of gibberellin during any period improved this coefficient compared to the control. The results indicated that the application of GA3 with concentrations above 25 ppm can improve the growth of saffron and increase its yield under the semiarid climatic conditions of eastern Morocco.

Comparing annual and biennial crop cycle on the growth, yield and quality of saffron using three corm dimensions

Saffron (Crocus sativus L.) is a geophyte plant belonging to the Iridaceae family and it is appreciated for its red dried stigmas used as cooking spice and flavouring agent. Effects of crop cycle length and mother corm dimension, as well as their interaction, have been evaluated on the flowering (morphological traits of flowers, days to flowering, flowering interval and flower production), quantitative traits (stigma and daughter corm yield), vegetative development (leaf and daughter corm traits) and qualitative characteristics (coloring, bittering and aromatic powers) of spice. A two-year field study (2017–2019) was conducted to compare annual and biennial crop cycle of saffron using three corm dimensional classes (D1: 2.0–2.5 cm, D2: 2.6–3.5 cm and D3: 3.6–4.5 cm) according a split-plot design with 3 replications. The results showed that the corms of D3 class, planted in annual crop cycle, produced flowers with the highest stigma length (42.2 mm), and dry weight of stigmas (7.4 mg), stamens (11.4 mg) and tepals (40.7 mg). The highest number of flowers per m2 (311.8) and stigma yield (20.7 kg ha−1) were found when corms belonging to D2 class were planted in biennial crop cycle, meanwhile the highest daughter corms production (35.9 t ha−1) was obtained when corms belonged to D3 class were planted in annual crop cycle. Number of daughter corms per m2 with a horizontal diameter from 3.1 to 4.5 cm and weight from 10.1 to > 25 g decreased as increasing the crop cycle length. In biennial crop cycle, corms of D1 class produced more daughter corms belonged to 3.1–3.5 cm diameter class and to 15.1–20 g weight class compared to D2 and D3 classes. Regarding to the spice quality, coloring and bittering powers were positively influenced by biennial crop cycle. According to International Standardization Organization (ISO 3632) references, the maximum values of color (306.3 A1cm1% 440 nm) and taste (116.2 A1cm1% 257 nm) were reached in spice obtained from “biennial crop cycle x D2 class” interaction. No significant effect of all experimental factors on aromatic power was found. It was concluded that the evaluation of combination between crop cycle length and corm dimension is necessary in the saffron management in order to achieve the optimum yield of stigmas and corms, to improve the qualitative traits of spice and to enhance the by-products as corms of D1 class.

Effect of gypsum and micronutrients on spike and corm yield of gladiolus (Gladiolus grandiflorus ) cv. Guvari

Gladiolus is a nutrient responsive crop that requires major and micro-nutrients viz. N, P, K, Zn, Mn, Fe, B, along with gypsum significantly improves the growth, flowering, yield and quality of corms. In addition, gypsum acts as a source of calcium and soil loosening factor that is needed for corm development. Hence, field experiment was conducted during 2019-2020 at Department of Horticulture, Annamalai University, Tamil Nadu, India on gladiolus cv. Guvari to maximize the yield and quality of spikes and corms. The treatments comprised of ten different combinations of recommended dose of fertilizers (120:150:150 kg/ha NPK), Gypsum (100, 200 and 300 kg/ha) and foliar application of FeSO4, MnSO4 ZnSO4 and HBO(0.5% each in single spray on 30 days 44, 4 33 after planting (DAP) and two sprays on 30 and 45 DAP laid out in Randomized Block Design with three replications. The growth, flowering, and corm yield parameters were periodically assessed. The results revealed that application of gypsum and micronutrients significantly increased the vegetative growth, flowering, spike yield, and corm yield. Application of 300 Kg/ha gypsum was found effective when compared to low doses. Among the ten treatments, application of 120:150:150 kg/ha NPK + 300 kg/ha Gypsum + foliar spray of (0.5% each) FeSO4, MnSO4 ZnSO4 and H3BO3 at 30 and 45 DAP found most 44, 4 33 effective with higher plant height, leaf area, root dry weight, dry matter production, spike length, floret diameter, spike yield, and number of marketable spikes per plant. The corm yield parameters including corm weight, number of daughter corms per plant, number of cormels per plant and weight of daughter corms were also superior in this treatment. Hence, it is confirmed that the application of 300 kg/ha gypsum + foliar spray of (0.5% each) FeSO4, MnSO4ZnSO4 and H3BO3 at 30 and 45 days after planting P along 44, 4 33 with 120:150:150 kg/ha NPK proved maximizing the spike and corm yield of gladiolus.

Crocus sativus L. Ecotypes from Mediterranean Countries: Phenological, Morpho-Productive, Qualitative and Genetic Traits

The characterization of C. sativus ecotypes is of great interest for preserving them from a possible genetic erosion due to the decrease of European cultivation surface. In this study, we evaluated four ecotypes from Italy (Sardinia and Abruzzo), Spain (Castilla-La Mancha), and Greece (Kozani) in order to detect the existence of variability and promote the biodiversity of this crop. Thirty-one traits related to saffron flowering, flower morphology, production of spice and daughter corms, vegetative development (leaf and corm traits), and spice quality, were evaluated. In addition, a genetic analysis through three PCR-based approaches, SSRs, RAPD, and SRAP was assessed. Results highlighted a phenotypic variation among ecotypes during two consecutive years. All the studied parameters were influenced by the ecotype except for the stamen length, color coordinates of tepals, leaf length, and leaf number per plant. Sardinia had a longer flowering interval, earlier flowering, and higher spice yield and quality than the other corm origins. The maximum values of morphological traits, such as stigma length, dry weight of stigmas, tepals, flowers and leaves, leaf area, and daughter corm weight were observed in the Abruzzo ecotype. Principal component analysis (PCA) showed a clear separation among ecotypes, in which Sardinia and Spain showed more similarities than Abruzzo and Kozani. Significant negative correlation was found between days to flower with stigma yield and quality. However, we could not find molecular markers discriminating among corm origins. In conclusion, this study suggests the importance of C. sativus ecotypes as precious source of biodiversity and bioactive compounds, and of their enhancement as fundamental prerequisite for a sustainable development strategy and as an agricultural diversification opportunity for growers.

Field evaluation of PGP Bacillus sp. strain D5 native to Crocus sativus, in traditional and non traditional areas, and mining of PGP genes from its genome

Native Bacillus sp. strain D5 coded as (Bar D5) has been isolated from the saffron corm that showed plant growth promotion (PGP) properties and also inhibits the growth of corm rot causing Fusarium oxysporum R1 (Fox R1) in-vitro. Bar D5 was more efficient PGP bacterium in comparison to earlier reported native bio-formulations by our group. Pot assays and field evaluation of Bar D5 confirmed its in-vivo efficacy for PGP traits and biocontrol activity as well. Pot trials were followed by field trials at traditional (Kishtwar) and non-traditional (R.S Pura) saffron cultivation areas in Jammu and Kashmir. At both places, Bar D5 bio-formulation treatment led to the increase in root number & length, shoot number & length, flower number and number & weight of daughter corms. Additionally, it also decreased the corm rot disease incidence significantly. Priming of corms with bio-formulation resulted in the reduction of pathogenic fungal load by three fold at the depth of corm sowing from ground level. The shelf life/viability of Bar D5 based bio-formulation was found to be 52% (viable spores) for one year at room temperature. Draft genome sequence of Bar D5 revealed the presence of genes necessary for PGP and biocontrol activity. Further, confirmation of gene sequences and annotation was done by amplification, re-sequencing and mapping of PGP and biocontrol genes on draft genome. Bar D5 based bio-formulation can be provided to companies/researchers interested in saffron cultivation or bio-formulation production for commercial exploitation, since saffron is grown as revenue crop across continents. The present study bridges the gap between genomics and its field application.

Corm Rot of Saffron: Epidemiology and Management

Saffron, comprising of dried stigmas of the plant known as Crocus sativus, is one of the most important and scantly cultivated agricultural products. It has been used as a precious spice for the last at least 3500 years. Due to its numerous medicinal qualities and pharmacological applications, it is considered as a “golden condiment”, and its demand and consumptions has risen over a period of time. Although efforts are continuously being made to enhance the productivity in the traditional areas and promote the cultivation of saffron in the newer areas, there are several constraints hindering these efforts. Prevalence of corm rot is one such limiting factor which results in the reduction in saffron production and decline in the area under its cultivation. The disease not only reduces the yield substantially, but also adversely affects the production of daughter corms. Complete understanding and knowledge about the disease is still lacking due to the inadequate information about its etiology and epidemiology. Moreover, due to the non-availability of resistant genotypes and lack of improved cultural practices, presently no effective and sustainable management strategies are available. This review article gives an overall account of the history and impact of saffron corm rot, its present status, yield losses caused by it, dynamics of the pathogens associated with the disease, their survival and dispersal, factors influencing disease intensity, epidemiology and sustainable management strategies. As comprehensive information on the disease is presently not available, an attempt has been made to review the current knowledge regarding corm rot of saffron. The information about the disease discussed here can eventually be beneficial for the growers, students, researchers, plant protection organizations, development departments, extension workers, policy makers, government agencies and public organizations.

AGRONOMIC AND QUALITATIVE TRAITS OF SAFFRON AND CUMIN IN RESPONSE TO INTERCROPPING

As well as the expansion of land use due to the short period of saffron growth, its intercropping can also enhance yields and agronomic traits, which usually happens through weed control, shading, and the reduction of soil temperature and growth climate. Therefore, the effects of cumin seed rates in an intercropping on quantitative and qualitative characteristics of saffron were studied in a Randomized Complete Block Design (RCBD) with three replications in Zaveh, Torbat-E Heydariyeh, Iran, during 2016–2017. Treatments included five levels of cumin seed proportions (25, 50, 75 and 100% of the optimum density). The results of the study indicated the significant effect of cumin seed rates on all the measured traits of saffron except the number of flowers, daughter corms and leaves, as well as safranal value. The minimum and maximum weight of dry stigma was associated with the ratios of 100 and 25% of cumin seed, respectively. Any increase in the ratio of cumin seed by over 25% reduced the amount of other quantitative traits. The cumin seed ratio showed significant effects on the number of umbels per plant, the number of seeds per plant, and seed yield. Since the increase in the number of seeds per plant as a result of low ratios of cumin seed cannot compensate for the reduction of plants, therefore, lower yields would be attained. Totally, increasing shading and less competition, due to lower ratios of seed, improves physical, chemical and biological conditions of the soil, and helps to save more water. Such conditions improve the traits of corm, flower, and photosynthetic area, and so results in an economical saffron yield.

The Influence of Soil Physical and Chemical Properties on Saffron (Crocus sativus L.) Growth, Yield and Quality

Soil physical and chemical properties play a central role in plant growth, influencing the availability of air, nutrients, and water. The aim of this two-year study was to evaluate the effect of soil texture and chemical properties (pH, electrical conductivity, organic carbon, organic matter, total, and active lime) on saffron (Crocus sativus L.) growth, yield, and quality. Corms were planted in pots filled with seven different soil textures obtained mixing an increasing quantity (33% and 66%) of sand to a clay soil (S1) and to a clay loam soil (S2) compared to a full (100%) sandy soil as a control (S7). A randomized complete block design comprising of seven pots with different types of soil (S1, S2, S3, S4, S5, S6, and S7) replicated three times was used. The results showed that the highest flower number (320.3 n m−2), stigma yield (2.0 g m−2), daughter corm production (7.9 kg m−2), and horizontal diameter (3.1 cm) were derived from S3 and S4 soils. These were characterized by a loam and sandy-loam texture, not very calcareous, with a sub-alkaline and neutral pH, low electrical conductivity, a content of organic matter between 5.46 and 8.67 g kg−1, and a content of active lime between 21.25 and 26.25 g kg−1. According to International Organization for Standardization (ISO) references, although all spice samples belonged to the first qualitative category, S1, S3, and S2 soils recorded the highest value for coloring power (290.5, 289.1, and 287.6 A1%1cm 440 nm, respectively). The highest values of bittering (109.2 A1%1cm 257 nm) and aromatic (26.6 A1%1cm 330 nm) power were reached by S3 soil. Positive correlations were found both between color with clay and organic matter, and aroma with total calcium carbonate. In conclusion, the assessment of soil conditions is particularly important to obtain the best saffron performance in terms of stigma and daughter corms yield as well as spice qualitative traits.

The Effect of 24-Epibrassinolide Treatments at Different Concentrations on Some Growth Parameters and Crocin Level in Saffron (Crocus sativus L.)

Brassinosteroids (BRs) are steroid phyotohormones that play roles in plant growth, secondary metabolite accumulation, stress response, and adaptation. Saffron (Crocus sativus L.) is an important plant with significant pharmacological effects due to its rich phytochemical content. Crocin, the main pigment of the saffron stigma, is a natural food colorant and has anti-cancer activity. In this study, the effects of 24-Epibrassinolide (EBL) at different concentrations (10-6, 10-7, 10-8 and 10-9 M) on corm (mother corm) and aerial part related parameters as well as the level of crocin in saffron were investigated. The experiment was conducted in a plant growth cabinet as randomized plots design with 3 replications. 24-Epibrassinolide treatments did not affect the rates of shoot emergence from saffron corms, while 10-8 and 10-9 M EBL treatments increased the number of active nodium and cormlet (daughter corm) as compared to control. All the applied EBL concentrations significantly increased the root and shoot lengths of saffron plants. The maximum number of flowers per plant was observed as a result of the 10-8 M EBL treatment. Exogenous treatment of 10-9 M EBL enhanced the crocin level by 96.0% compared to the control. This is the first study to evaluate the effects of BRs in saffron.

Exogenous gibberellic acid application influences on vegetative and reproductive aspects in gladiolus

Abstract Ornamental plants like gladiolus are suitable option for growers with lower amount of land, as they are highly economic and have lower cost of production. An experiment was conducted with aim to study the exogenous application influence of gibberellic acid on vegetative and reproductive characteristics of gladiolus was conducted under the subtropical conditions. The experiment was laid out in two factors randomized complete block design and replicated three times. Gibberellic acid (GA3) was used in different concentrations (0, 50, 100, 150, 200 mg L-1) to corms of two cultivars of gladiolus (‘White Prosperity’ and ‘Red Advance’). Results showed that most of the parameters were significantly influenced by gibberellic acid at 200 mg L-1. The maximum sprouting, number of leaves plant-1, daughter corms per plant, less number of days to corm sprouting, days to spike emergence and flower opening were recorded in plants treated with 200 mg L-1 gibberellic acid (GA3). ‘Red Advance’ produced more number of leaves plant-1, corm diameter, corm weight, and less number of days to spike emergence and flower opening. It can be concluded from the present findings that the treatment of corms with 200 mg L-1 gibberellic acid can improve the growth and yield of cultivar Red Advance than White prosperity under the subtropical conditions.

Nutrition Management and Farm’s Age Affect Saffron Daughter Corms Behavior, Nutrients Uptake and Economic Water and Fertilizer Use Efficiency: A Large Scale On-farm Experiment in Torbat Heydarieh, Iran

ABSTRACT Evaluation of the relationships between nutritional patterns and farms’ age with the behavior of saffron (Crocus sativus L.) daughter corms based on farmers’ management (on-farm) can be crucial in improving saffron sustainable yield. Furthermore, in commercial saffron production, especially in small farms, the purchased water and fertilizers are the basis of sustainable saffron profitability, hence, recognizing the relationships between economic water use efficiency (EWUE) and economic fertilizer use efficiency (EFUE) can be important. An on-farm experiment was conducted on a large scale based on farmers’ management in Torbat Heydarieh, Iran. The farms’ age (1–6 years old) and fertilizers management approaches (organic, mineral and integrated) were considered as the first and second factors, respectively. Large-sized daughter corms number and weight and corms N and P content increased with increasing farms’ age from 1 to 4 years old. However, these parameters decreased with increasing farms’ age from 4 to 6 years old. Irrespective of saffron farms’ age, the minimum large-sized daughter corms number and weight were observed when mineral fertilizer management was practiced. By contrast, the maximum values were related to integrated fertilizer management. In each type of fertilizer management, EWUE and EFUE (based on large-sized daughter corms monetary value) increased with increasing farms age from 1 to 4 years. However, increase in farms age from 4 to 6 years caused a significant reduction in mentioned indices. Overall, if high-quality saffron corm production is needed, corms should be harvested in the fourth year to gain the maximum yield and profit.

Depending on mother corm size, the removal of extra lateral buds regulates sprouting mechanism and improves phosphorus acquisition efficiency in saffron (Crocus sativus L.)

Low P solubility in arid and semi-arid regions dominated by alkaline or calcareous soils is known as a main limiting factor for sustainable saffron (Crocus sativus L.) production. Hence, it may be necessary to consider efficient approaches for improving P uptake mechanism. The effects of lateral buds removal and mother corm size on daughter corms behavior, flower yield and P acquisition efficiency (PAE) were studied in saffron grown in a P-deficient soil in a two-year field experiment during 2017–2018 and 2018–2019 growing seasons. The 16 main plots [lateral bud removal (no removing lateral buds as control, keeping apical bud + removing all lateral buds, keeping apical bud + 1 lateral bud, and keeping apical bud + 2 lateral buds) × mother corm size (4.1–6.0, 6.1–8.0, 8.1–10.0, and 10.1–12.0 g)] and 2 sub-plots (first and second sampling) were conducted based on a randomized complete block design arranged in factorial-split with 3 replicates. The maximum leaf area, flower number, and dried stigma yield were observed by keeping 2 lateral buds on mother corm. By contrast, the minimum values were obtained in control treatment. Furthermore, keeping 1 or 2 lateral buds alleviated the adverse effects of small-sized mother corm on leaf and flower related traits. Large-sized daughter corms (> 10.0 g) constituted 25.0, 22.5, and 22.1% of the total number of daughter corms, respectively, when 0, 1, and 2 lateral buds were kept on 10.1–12.0 g mother corms. The highest P concentration in large-sized daughter corms (3.72 g kg−1) and PAE (38.89%) were obtained by keeping 2 lateral buds on 10.1–12.0 g mother corms, while the lowest values (2.66 g kg−1 and 6.77%) were observed by planting 4.1–6.0 g untreated mother corms. It can be concluded that the sprouting mechanism in saffron is controlled by mother corm size. In sum, considering the cultivation of saffron in arid and semi-arid regions, selecting 10.1–12.0 g mother corms treated for keeping 2 lateral buds is recommended.

Nutrient availability and saffron corms growth affected by composted pistachio residues and commercial poultry manure in a calcareous soil

ABSTRACTUtilizing the proper techniques of plant residue composting can play a significant role in reducing the adverse environmental impacts of chemical fertilizers. Herein the effects of commercial poultry manure (CPM) and composted pistachio residues (CPR) on nutrient availability and saffron daughter corms behavior in a calcareous soil were evaluated as a greenhouse experiment based on completely randomized design arranged in factorial with three replicates. In this study, CPM rates (0, 3, 6, and 9 t ha−1) and CPR levels (0, 20, 40, and 60 t ha−1) were assigned as the first and the second experimental factors, respectively. From the results, CPM or CPR application caused a significant increase in small (≤5 g), mid (5.1–10 g) and large-sized (10.1–15 g) daughter corms number. The highest N (P) concentration in small, mid and large-sized daughter corms was recorded when 9 t ha−1 CPM was applied along with 60 t ha−1 CPR. Soil organic carbon content increased with increasing CPM or CPR levels. The same trend was also observed for soil available N, P, K, and electrical conductivity. By contrast, CPM or CPR levels caused a significant reduction in soil pH. According to the results, pistachio compost can be considered as an eco-friendly alternative to chemical fertilizers to improve soil fertility in saffron farms.

Study of diversity in some Moroccan population of saffron (Crocus sativus L.).

To study Moroccan saffron germplasm variability relating to different agro-morphological and phenological traits, 969 saffron corms (accessions) were collected from thirteen different sites located in traditional saffron area of Taliouine-Taznakht. The study confirmed a wide range of phenotypic variability within and between populations. The variance analysis revealed that the mother corm weight (MCW), taken as covariant, has significant effect on all studied traits. The difference within and between origins (Provenances) was highly significant for all traits, which showed highly significant correlation. The flowers number (NF) as well as the number of daughter corms weighing above 7 g per plant (NDC≥7) turned out to be the most determinant parameters of saffron yield. The produced FN per corm varied from 1 to 9 with an average of 2.2 flowers. P1 population recorded a flowering rate of 65.5% with a maximum average of NF (2). Stigmat length (SL), which is an important yield trait, showed wide variation between origins from 32 to 38 mm. The mean stigma dry weight (DSW) varied from 4.2 to 6.2 mg with a maximum of 7.1 mg per flower recorded in P1. The PCA revealed 5 homogeneous main groups inside the studied populations. The first one was monoorganogenic and consisted of P1 population only, a group characterized by high values of MCW, NF, NDC≥7 and DSW. This study confirms as well a noticeable influence of corm origin on saffron yield, explained by the genotypic profile and/or the epigenetic effects of the different origins. These results proved a variability which should be useful to the selection program aiming the improvement of saffron productivity in Morocco. Key words: Variability, agro-morphological traits, phenological traits, saffron corms, Morocco.

Influence of gibberellic acid on vegetative, floral and corms yield of gladiolus cultivars under the agro-climatic condition of Peshawar-Pakistan

Abstract Gladiolus is an important cut flower commercialized in Pakistan, and the use of gibberellic acid (GA3) to cultivate it in the Peshawar valley may promote the production of high quality flower spikes. Therefore, an experiment “Influence of Gibberellic acid on vegetative, floral and corm yield of gladiolus cultivars” was conducted under the climatic condition of Peshawar, during 2016. The experiment was laid out in two factors Randomized Complete Block Design there were five treatments replicated three times. Factor “A” was the gibberellic acid (GA3) concentrations i.e. 0, 50, 100, 150, 200 mgL-1 Factor “B” was the two cultivars of gladiolus i.e., White Prosperity and Red Advance. It revealed from the results that most of the parameters were significantly influenced by gibberellic acid at 200 mgL-1. The maximum sprouting percentage (96.25), number of leaves plant-1 (10.6), number of floret spike-1 (14.4), number of shoots plant-1 (3.17), number of daughter corm plant-1 (3.54) and survival percentage (88.50), less days to corm sprouting (17.9), number of days to spike emergence (48.83), days to floret opening (72.73) were recorded in plants treated with 200 mgL-1 of gibberellic acid (GA3) concentration. Whereas, the maximum plant height (75.62 cm), length of spike plant-1 (57.15 cm), corm diameter (3.37 cm) corm weight (14.90 g) were recorded in plants treated with 150 mgL-1Gibberellic acid. Red advance produced more number of leaves plant-1 (9.89), number of shoots plant-1, (2.69) corm diameter (3.04 cm), corm weight (13.03 g), survival percentage (70.9), less number of days to spike emergence (53.8) and days to floret opening (74.5). It can be concluded from the present findings that the treatment of corms with 200 mgL-1gibberellic acid can improve the growth and yield of Red Advance cultivar of gladiolus under the agro-climatic conditions of Peshawar valley. Keywords: Corm yield; Flower production; Gibberellic acid; Gladiolus cultivars; Vegetative growth http://dx.doi.org/10.19045/bspab.2018.700217

Plant growth promoting bacteria associated with corm of Crocus sativus during three growth stages.

Corm, being a unit of reproduction and storage, plays an indispensable role in the life cycle of Crocus sativus (saffron). This study deals with the screening of bacteria isolated from cormosphere (area surrounding the corm sheath) of C.sativus during three growth stages for biofertilizer and biocontrol property. Out of 1000 protease producing bacteria isolated from the cormosphere (soil adhering corm sheath in analogy to rhizosphere), three plant growth promoting (PGP) Bacilli namely Bacillus thuringiensis DC1, B.megaterium VC3 and B.amyloliquefaciens DC8 were selected based on multiple and maximum PGP traits along with corm rot pathogen antagonism. To evaluate invivo efficacy of the consortia, pot trials were conducted and a significant increase in number and length of both, shoot and root were observed. Further, the disease incidence in test corms was reduced by threefold as compared to control and the number of daughter corms produced in pot trials was also increased. Since corm is a unit of reproduction/propagation, increase in its number is of major significance. This is the first report on isolation and characterization of Plant growth promoting bacteria from any cormosphere.

Propagation of Hypoxis hemerocallidea by inducing corm buds

African potato is facing rapid decline of wild populations due to large-scale harvesting, necessitating efficient means of propagation. Propagation of African potato is difficult due to seed dormancy and the species does not naturally propagate easily from corms. This study aimed to develop a simple and affordable propagation protocol for African potato. Chipping, scooping and cross-cutting methods were used to expose buds on small, medium and large African potato corms. There were no significant differences in number of ‘daughter corms’ between chipping and scooping for the large corms, as well as chipping and scooping for medium and small corms at the end of the experiment. Cross-cutting did not lead to formation of ‘daughter corms’. The number of leaves on ‘daughter corms’ was only significantly higher in the scooped medium corms compared with chipped small corms at the end of the experiment. Chipping showed a significantly higher number of roots compared with scooping. The chipping and scooping methods resulted in fully developed ‘daughter corms’ planted individually. These methods can be recommended for multiplication of African potato corms. This study provided novel and relatively affordable methods for in vivo multiplication of African potato, which can potentially help conserve wild populations.

Effect of colchicine and corm weight on daughter corm formation in saffron (Crocus sativus L.)

Effect of colchicine and corm weight on daughter corm formation in saffron (<i>Crocus sativus</i> L.)

Correlation and path analysis studies in Gladiolus (Gladiolus hybrids Hort.)

Correlation and path analysis were carried out in 12 varieties of gladiolus for different yield attributing traits at the Horticultural Research Station, Tamil Nadu Agricultural University, Yercaud. The results indicated that the Rachis length was positive and significantly correlated with mother corm weight (g), plant height at 60th days after planting (DAP) (cm), number of leaves per plant at 60th (DAP), length of spike (cm), weight of daughter corm (g) and vase life (days). But, it is negative and significantly correlated with number of days taken for first floret opening (rg: -0.714 &amp; rp: -0.664), number of daughter corms per plant (rg: -0.826 &amp; rp: -0.724) and marketable spikes per plant (rg: -0.561 &amp; rp: -0.418) at both genotypic and phenotypic levels. For path analysis the residual effect was 0.174 and it was evident that the highest direct effect on length of rachis was observed in case of mother corm size (0.951) and weight of the daughter corm (0.943), followed by number of daughter corms per plant (0.859), number of florets per spike (0.849), length of first floret (0.832), marketable spikes per plant (0.385), number of leaves per plant at 60th DAP (0.384), diameter of first floret (0.374) and length of spike (0.221) under Shevaroys conditions

Saffron Daughter Corms Formation, Nitrogen and Phosphorous Uptake in Response to Low Planting Density, Sampling Rounds, Vermicompost and Mineral Fertilizers

ABSTRACTHigher planting densities increase flower yield of saffron during the initial years; however, increase in population may have a negative effect on daughter corms, through increasing competition for nutrients. Accordingly, lower densities result in more desirable daughter corms for future planting. To investigate the effect of planting density, vermicompost and mineral fertilizers on daughter corms formation, and nitrogen (N) and phosphorus (P) content in the corms during different phenological stages, a three-year field experiment was conducted as factorial-split layout based on randomized complete block design with three replications, at Faculty of Agriculture, Ferdowsi University of Mashhad, Iran. The experiment consisted of 12 main plots [planting density (30, 60, 90 and 120 corms m−2) × fertilizer sources (vermicompost 10.2 t ha−1, mineral fertilizer including N 225 kg ha−1 + P 129.08 kg ha−1 and control)] and 15 subplots (15 sampling rounds; during the first, second and third growing seasons). During all stages of sampling, N and P content in large-sized daughter corms was significantly higher compared with middle and large-sized daughter corms. Application of vermicompost significantly increased the number, weight, N and P contents of medium and large daughter corms per plant than mineral fertilizer. Increase in plating density caused a significant reduction in number, weight, N and P content in the medium and large sized daughter corms per plant. Overall, the results suggest that lower densities and vermicompost application should be scheduled in mother corms production programs.