Fresh Seeds Research Articles

Seed Quality of Lablab Bean (Lablab purpureus) as Influenced by Seed Maturity and Drying Methods

The lablab bean or ‘Kacang sepat’ is a food crop originating from India and is commonly found in tropical areas such as Indonesia, Thailand and the Philippines due to its adaptability. However, in Malaysia, lablab is grown as a backyard crop, and the area cultivated with this crop is still limited. Lablab has the potential to become a commercial vegetable crop in Malaysia due to its high protein content (18–25%). Therefore, to increase lablab cultivation, good quality seeds are a prerequisite. A key factor in the production of quality seeds is the ideal harvest time of the pods during seed development and maturation and based on identifiable characteristics. The first part of this study was conducted to assess the physical characteristics of lablab pods and seeds of the cultivar Highworth (MDI 12842). Plants were grown using standard cultural practices. Pods and seeds were collected at ten different maturity stages (5, 10, 15, 20, 25, 30, 35, 40, 45, and 50 days after anthesis (DAA)). Pods and seeds showed a significant difference in size and colour at different maturity stages. Seeds harvested at 20 DAA had maximum pod and seed size. The seeds attained physiological maturity (PM) at 30 DAA when the pod colour is light reddish brown and, after being subjected to sun and oven drying, gave maximum germination percentages of 89% and 91%, respectively, while fresh seeds had only 78% germination. Results indicated that the germination percentage of lablab improved, regardless of the drying method used. Therefore, the lablab bean pod colour is a suitable indicator to be used as an easy method for the identification of the best time for pod harvesting for seed production.

Effects of seed extracts of turmeric (Curcuma longa linn) on Escherichia coli and Streptococcus species isolated from urine of patients in Wukari, Taraba State, North East, Nigeria: Prospective antimicrobial alternative for Urinary Tracts Infections

Antimicrobial activity of different herbal extracts in different regions of the worlds has been established as a panacea to the advancement of effective chemotherapy against resistant bacteria. Seed extracts of turmeric as one of the antibacterial agents has been examined to this effect. Turmeric (Curcuma Longa, Linn), is one of the most useful herbal medicinal plants owing to its biological active component Curcuminoids, which are natural phenols. Turmeric has shown to be effective as anti- inflammatory, anti-oxidant, antifungal, antiulcer, and anticancer, thus has a potential against various malignant diseases such as, diabetes, allergies, arthritis, Alzheimer’s disease and other chronic diseases. This study examined the antibacterial activity of turmeric seed against Streptococcus species and Escherichia coli isolated from urine samples of patients. The antibacterial activities of aqueous and ethanolic extracts of dried and fresh turmeric seed was tested on the organisms using standard bacteriological technique. The zone of inhibition was more significant on the ethanolic extract of the fresh seeds and at a higher concentration (15g – 80ml and 20g – 100ml) on both organisms. Also, on both organisms, the result obtained revealed resistance of isolates to the aqueous extracts of the dried seed with heavy and moderate growth. In conclusion, the results obtained from the turmeric extracts shown considerable antimicrobial activity against Streptococcus species and Escherichia coli and can be used as a broad spectrum natural antimicrobial alternative for treating Urinary Tracts infections.

EFFECT OF DIFFERENT CONCENTRATION OF ETHREL ON GERMINATION OF SUNFLOWER SEEDS (Helianthus annuus L.) AT BHARATPUR, CHITWAN, NEPAL

The research was carried out on “Effect of different concentrations of ethrel on germination of sunflower seed at the Agronomy laboratory in Nepal Polytechnic Institute, Bharatpur, Chitwan from December 2015 to January 2016. The experiment was laid out in Completely Randomized Design (CRD). In the present investigation, seed samples of sunflower (Helianthus annuus) variety viz. Modern Dwarf was collected from the National Oil Research Program (NORP) Nawalpur, Sarlahi for the experiments. Soaking of seeds in water, seed treatment with ethrel (@0.3ml/lit and 0.4ml/lit concentration), hot water treatment, mechanical clipping and control (without treatment) were done to see their effect on the germination of sunflower seed. The recorded parameters among the sampled seeds were germination percentage, root length, shoot length, fresh weight and dry weight. The seeds soaked for 12 hours germinated maximum (100.00%) and seeds that are boiled in water for 15 minutes germinated minimum (4.8%) on the 3rd, 6th and 9th days of observation. Maximum root and shoot length of germinated seed was found in seeds without treatment i.e. 8.5cm & 5.575 cm and minimum root and shoot length was found in seeds boiled in water for 15 minutes i.e. 0cm. Similarly, seeds without treatment and seeds boiled in water for 15 minutes showed the maximum fresh and dry weight (2.790gm & 0.488gm respectively) and seeds boiled in water for 15 minutes & seeds without treatment showed the minimum and dry weight (0.913gm & 0.289gm respectively) on the 9th day of observation. The results also showed that the seeds treated with ethrel (@0.3ml/lit) germinated (91%) with significant root & shoot length and fresh weight (4.55cm, 5.25cm and 2.537gm respectively).

Morfološke osobine biljke i reproduktivna sposobnost semena hajdučke trave (Achillea millefolium L.) u zavisnosti od pedo-ekoloških uslova

The paper analyzes the influence of soil type and its agrochemical characteristics on the morphological and productive parameters of different yarrow (Achillea millefolium L.) populations. At 8 locations the following fertility parameters were analyzed: pH (H2 O), pH (KCl), CaCO3 (%), humus (%), total N (%), available P2 O5 and K2 O (mg 100 g-1 soil). From the morphological parameters, the following were measured: plant height, number of leaves, number and diameter of the head, from the productive parameters, the fresh above-ground masses per plant, the fresh above-ground masses and seeds yield per hectare and the harvest index were analyzed. Among the quality parameters of yarrow seeds, germination energy, total germination and weight of 1,000 seeds were examined. The largest number of heads (13.6), a diameter of heads (1.9 cm) and seed yield (386.0 kg ha-1) had the population of yarrow from the location Pančevo (Am1). In this variant, seeds with the highest germination energy (48.8%) and total germination (53.4%) were obtained. The population in this locality was in second place in fresh above-ground masses yield (15,604.0 kg ha-1). The highest fresh above-ground masses yield per hectare, was obtained in variant Am5 (location Starčevo "rit"). The lowest values of morphological and productive parameters and the weakest quality of seeds were found in the yarrow plants originating from soils with less natural fertility and soils located in urban areas.

УРОЖАЙНІСТЬ ЕСПАРЦЕТУ (Onobrychis arenaria L). ПІЩАНОГО В УМОВАХ ПРАВОБЕРЕЖНОГО СТЕПУ УКРАЇНИ

The results of scientific research conducted in 2017–2019 by the Institute of Agriculture of the Steppe NAAS in the nursery of competitive variety trial under the selection and seed crop rotation with 12 breeding numbers of Hungarian sainfoin are presented. All these samples were analyzed for fresh mass yield, seed yield and dry matter content. It was found that a cultivar No. 12 (breeding material of Kostiantyn variety) provided a stable significant increase at 3.2–12.4 t/ha, or 28.3–23.8 % compared to the Smarahd standard variety during three years study. On average, over the years of research, the dry matter yield of this selection number was maximal. The increase to the indicator of the Smarahd standard variety was 1.31 t/ha, or 12.00 %. The Hungarian sainfoin spread depends largely on the development of new more productive varieties with high quality and at the same time well adapted to different growing conditions. Proper selection of varieties is extremely important to solve the problem of increase in the yield and Hungarian sainfoin resistance to adverse environmental conditions. The research results revealed that seed productivity of cultivar No. 12 (breeding material of Kostiantyn variety) in the competitive variety trial was significantly higher, and the seed yield exceeded the standard variety by 0.31 t/ha, or 26.3 %. According to the research results of competitive variety trial on fodder and seed productivity of selection numbers, which were sown in 2017, it was selected the cultivar No. 12 (breeding material of Kostiantyn variety), which was characterized by high yields of fresh mass and seeds, and increased indicator of dry matter yield. Keywords: sainfoin, selection numbers, cultivar, competitive variety trail, yield, dry matter yield, seeds.

Standardization of propagation methods in minor wild fruit crops

The study was carried out to find out the ideal propagation techniques of wild and minor fruit crops at ICAR-IIHR, Bengalure, during 2016–19. Two year's data revealed that fresh seeds of most of the species, viz. karonda (Carrisa carandas), wood apple (Feronia limonia syn. Limonia acidissima) avocado (Persea americana) noni (Morinda citrifolia) wild jamun (Syzygium cumini) Alangeum (Alangium salvifolium) carombola (Averhoa carambola), Canito (Chrysophyllum cainito), bael (Aegle marmelos) kokum (Garcinia indica), yellow mangosteen (Garcinia xanthochymus) and Malabar tamarind (Garcinia gummigutta) did not have dormancy and their germination was more than 60 per cent. Although the days taken for germination varied in these fruits. Some fruits, viz. mulberry (Moris alba) gave good response (80%) for multiplication through cuttings. Air-layering was found successful in Governor's plum (Flacourtia indica) Karonda (Carrisa carandas) natal plum (Carrisa macrocarpa), Citrus hindsi Surinam cherry (Eugenia uniflora) and West Indian cherry (Malpighia emarginata) with 75% and 60% survival. The grafting was found successful (90%) in avocado (Persea americana) and wood apple (Feronia limonia)

Domestication of “Deguai” (Saurauia bontocensis Merr.) at La Trinidad, Benguet, Philippines

“Deguai” (Saurauia bontocensis Merr.) is an indigenous wild fruit-bearing tree in the Cordillera Administrative Region (CAR), Philippines. Due to rampant and continuing conversion of its habitat into agricultural and other uses, its population has become low, and its distribution has narrowed considerably. Thus, conserving and domesticating this endemic species by establishing propagation techniques and mini-tree plantations is timely and crucial. Results showed that deguai could be readily raised by sowing fresh seeds in heat-sterilized loam soil without pre-germination treatments. It took 22 d from sowing to start and 48 d to end the germination, with a mean germination percentage of 39.60. Moreover, transplanted seedlings in various media combinations showed significant growth differences in root collar diameter (RCD) and length of primary and secondary roots but not on their height and number of secondary roots. Compost in combination with either topsoil or sand significantly emerged as the most suitable media for the growth of the studied seedlings. Stem cuttings grew best untreated rather than applying rooting hormones such as alpha-naphthalene acetic acid (ANAA) and Hormex. This result was manifested in the significantly high survival rate, numerous developed buds, and longest newly developed shoots of untreated cuttings. Stem cutting section treatment significantly affected the number of developed buds only, where base cuttings had the most. The mini-tree plantation established using rooted stem cuttings was successful with a high survival rate of 89.26% after 5 yr from field planting and with four deguai trees bearing fruits for the first time after 7 yr from field planting. The nursery-grown seedlings planted in the mini-tree plantation have exhibited a 99% survival rate nine months after outplanting. Thus, deguai can be domesticated in the new habitat for fruit production, improvement of the environment, and biodiversity conservation. Monitoring of the trees continues, and a study toward generating a fruit production-enhancing technique for the species is readied for implementation.

Diversity of the Seed Material of Selected Plant Species of Naturally Valuable Grassland Habitats in Terms of the Prognosis of Introduction Success

The current conservation status of semi-natural grassland habitats in Poland indicates that actions for their restoration are necessary. Many of the degraded sites require the introduction of diaspores of representative species because other methods of improving their condition are not sufficiently effective. Meanwhile, little is known about the diaspores of native wild-flower species and the biology of their seeds. The aim of the present study was to find an answer to the question of which features of the seed material can guarantee the success of the introduction. The study covered 28 plant species of 4 non-forest natural habitats (codes: 6440, 6410, 6510, 6210) occurring in river valleys. Diaspores were collected in 2015–2017. Morphometric measurements of diaspores were performed, the weight of 1000 diaspores was determined and the germination capacity analysis was carried out in accordance with ISTA Rules. The analysis was made with the division into normal seedlings, abnormal seedlings, dead seeds and fresh ungerminated seeds. Species with similar parameters of seed material were selected using the method of hierarchical clustering and PCA analysis. Three groups of species were distinguished: (1) with good seed germination capacity (above 65%), which, regardless of weather conditions during the generative development, and despite the small size of diaspores, can guarantee successful introductions (Verbascum thapsus, Veronica longifolia, Daucus carota, Plantago lanceolata); (2) species of little suitability for introduction, due to the large proportion (over 50%) of dead seeds (Armeria maritima, Linaria vulgaris, Potentilla erecta, Centaurea stoebe, Sanguisorba officinalis, Cnidium dubium); (3) species with relatively large size of diaspores and low seed germination capacity, due to the high proportion of fresh ungerminated seeds which means dormant seeds (Lathyrus pratensis, Geranium pratense).

Effects of oral ingestion of hyoscyamine from Daturastramonium seeds on the hippocampus in adult Wistar rats (Rattusnorvegicus)

The study aimed to evaluate the effects of oral ingestion of hyoscyamine fraction of Daturastramonium seeds on the hippocampus in adult Wistar rats. Fresh seeds of D. stramonium were procured and fractionated using high-performance liquid chromatography (HPLC). Twenty-four healthy adult Wistar rats weighed 230±0.50 grams, were procured and divided equally into four groups for the experiment. The group one received an equivalent bodyweight of normal saline, while three other groups received 200, 400 and 800 mg/kgbwt of hyoscyamine fraction of D. stramonium respectively for three weeks. At the end of the experiment, the animals were subjected to memory test using Morris water maze (MWM) and Novel object recognition test (NORT) test paradigms. The data obtained were expressed as mean ± SEM and repeated measures ANOVA with Fisher’s multiple comparisons post-hoc tests were used to obtain mean differences using Minitab 17 (LLC., U.K.) statistical package software. P < 0.05 was considered statistically significant. There was a statistically significant increase in the exploration time (p = 0.031) and escape latency period (p < 0.001) in the novel object recognition and Morris water maze test between the groups in the treated compared to the control group. The CA3 region of the treated group showed significant neuronal lesions, cytoplasmic vacuolations, pyknosis and necrosis. . In conclusion, exposure to hyoscyamine fraction of D.stramonium at adulthood impaired memory in Wistar rats.

Yam seed system characteristics in Nigeria: Local practices, preferences, and the implications for seed system interventions

Yam is an important food and cash crop in Nigeria. The seed system is mostly farmer-based and its challenges and opportunities are not well documented. This study reports results of surveys, interviews, focus group discussions and participant observations that describe local practices characterizing yam cultivation and the farmer-based seed system in five states in Nigeria. Our findings show that ware and seed yam are dynamic and highly commercialized goods in Nigeria. There is a high demand for, and a high turn-over of, seed yam. The reasons for the high demand are the low multiplication rate and degeneration of seed yam which lead farmers to frequently acquire fresh seeds and replace varieties, investing significantly in the seed of ware yam. The study found some farmers specializing in seed yam production but less than expected for such a highly commercial crop. The market is the major source for off-farm sourced seed yam, and although completely informal, the seed yam sector is vibrant and well organized. The identification of strategically positioned farmers and traders can offer opportunities and entry points for introduction of new varieties and improved seed production techniques. Building on the existing farmer-based system is a more logical strategy than replacing it with formal structures and legislative regulation.

Exergy, energy, and sustainability assessments applied to RSM optimization of integrated convective air-drying with pretreatments to improve the nutritional quality of pumpkin seeds

Pumpkin seeds are generally discarded but they are a source of protein, fibers, and other nutrients. This paper aimed to define the drying conditions for obtaining the optimal effective diffusivity (Deff) by applying the RSM (Response Surface Method) and Box–Behnken design (BBD) and random search also focused on energetic, exergetic, and environmental assessments. Pumpkin seeds were subjected to pretreatments by immersion in NaCl solutions at 0, 2, 7, and 14 % (w/w), and blanching at 373 K during 0, 2, 7, 12, and 14 min. The pretreated samples presented shorter drying times than the non-pretreated ones at all temperatures studied. The optimal conditions are 356.8 K, 12.65 % NaCl, and 0.5 min. The lipid and protein contents did not show significant variations at the optimal conditions concerning fresh pumpkin seeds; however, the crude fiber contents decreased. The energetic and exergy efficiency of the dryer were 13.4 % and 41.77 %, respectively. The Improvement Potential (IP) and Sustainability Index (SI) values are associated with the losses of exergy. The CO2 emissions during the global process were 0.165 kg/kg of fresh seeds, and their values were related to the specific energy consumption.

The Opposite Roles of White Light in Regulating Germination of Fresh and Aged Seed in Tobacco.

Light is one of the important environmental factors for seeds to evaluate whether the natural environment is appropriate for germination and subsequent seedlings emergence. The mechanism of light-mediated germination is mainly concerned with fresh seeds (FS) of model plants but is poorly understood in aged seeds. Here, the effects of light on germination of FS and naturally aged seeds (NAS) in tobacco and their relationship with plant hormones gibberellins (GA) and abscisic acid (ABA) were investigated. The results demonstrated that light promoted and inhibited the germination of FS and NAS, respectively. GA and ABA were involved in the germination control of NAS, as well as in FS. However, light suppressed GA signal and stimulated ABA signal in NAS, whereas it stimulated GA signal and suppressed ABA signal in FS. In addition, light stimulated the GA accumulation and reduction in ABA in FS while inhibiting the increase in GA level in NAS. Together, the present study demonstrates that light has opposite effects on the germination of FS and NAS, which are closely related to the metabolism and/or signaling of plant hormones ABA and GA.

Embryo position of Castanopsis sclerophylla (Fagaceae) seeds with recalcitrant storage behavior differs from Quercus genus but response to desiccation shows no difference

In many but not all recalcitrant Quercus seeds, water loss during drying only occurs through the scar. Consequently, the embryo axis sitting on the opposite side of the scar is well protected from desiccation. However, whether such a mechanism is common throughout Fagaceae species is unexplored. Similarly, little is known about the desiccation response of other Fagaceae genera. Germination and desiccation tolerance of Castanopsis sclerophylla (Lindl. & Paxton) Schottky (Fagaceae) were studied by drying the seeds with silica gel. Fresh seeds had a moisture content (MC) of 36% and germinated to 92.5% when incubated at 15/20 °C. Drying seeds to 22.5% and 20.7% MC decreased germination to 27% and 5%, respectively, indicating that seeds are recalcitrant. X-ray computed tomography and photomicrographs showed that the embryo axis of C. sclerophylla is located just below the scar. Regardless of drying occurring either through only the scar or the whole pericarp, embryo drying was deemed unavoidable. Nevertheless, germination percentage during drying showed exceptional similarities with the other Fagaceae species.

Effect of different drying methods on drying characteristics and quality of Camellia oleifera seeds

In order to improve the drying efficiency and product quality, three drying methods of hot air (HA), hybrid infrared-hot air (IR-HA), and hybrid radio frequency-hot air drying (RF-HA) were used to dry fresh Camellia oleifera seeds. The results showed that the shortest drying time was needed, and the minimum shrinkage of C. oleifera seed cells was obtained under hybrid radio frequency-hot air drying than that under hot air drying and hybrid infrared-hot air drying. The oils squeezed from C. oleifera seeds dried by natural air (room temperature), hot air, hybrid infrared-hot air, and hybrid radio frequency-hot air were represented by AO, HAO, IR-HAO, and RF-HAO respectively. The dielectric constant, characteristic peak value of melting heat flux, acid value, and peroxide value of oils squeezed were compared and found that the values of the four indicators of IR-HAO were the highest, but the values of RF-HAO were the lowest. The RF-HAO contains more unsaturated fatty acids, and the quality of RF-HAO was better than that of HAO and IR-HAO. Hybrid radio frequency-hot air drying was the best among the three drying methods of fresh C. oleifera seeds. Practical applications Camellia oleifera seed oil is rich in a large number of fatty acids, of which the content of unsaturated fatty acids can be as high as 93%. The contents of linolenic acid in unsaturated fatty acids were higher than those in sesame oil and soybean oil. Different drying methods on the drying characteristics in this study, microstructure of C. oleifera seeds and the dielectric properties, melting point, acid value, peroxide value of C. oleifera seed oil are analyzed to select the suitable drying technology for C. oleifera seeds. This theory and achievement can provide theoretical guidance for the subsequent processing and storage of C. oleifera seeds.

Biochemical Assessment of Peas Pisum sativum Varieties

Seven peas (Pisum sativum L.) varieties different originated, i.e, X07P54, X06PWY, NDPO80138-B-2, CA1P, L020140, Wt6803 and Mir were studied. Biochemical assessment of fresh aboveground biomass and seeds of peas varieties were done. At the beginning of flowering stage the NDPO80138-B-2 and X07P54 were reported high levels for crude protein (22.33% and 21.87%), crude fibre (25.94% and 25.76%) and crude ash (10.39% and 9.47%). In technical maturity with high crude protein and crude fibre contents NDPO80138-B-2 (21.59% and 21.38%), X06PWY (19.95% and 21.36%), X07P54 (19.78% and 20.57%) and CA1P (19.60% and 22.53%) were distinguished; by calcium CA1P (2.09%), and by phosphorus Wt6803 (0.54%). More significant variability in phosphorus content (21.27%) and Ca:P ratio (25.65%) in fresh biomass was observed. The lowest coefficient of variation was found for crude fibre (5.43%), crude ash (7.81%) and crude protein content (9.00%). The variability of parameters in technical maturity was found low and ranges from 2.34% for crude protein to 9.27 for phosphorus. The green mass yield is positively correlated with the calcium content (r = 0.581), phosphorus (r = 0.316) and crude ash (r = 0.077) and the seed yield positive correlated with calcium content (r = 0.79). The relationships found between qualitative indicators could be used in the breeding programs of peas.

H2O2 as a better index of seed quality and mechanism of cucumber (Cucumis sativus) seed deterioration

The present investigation was conducted at research farm of ICAR-Indian Agricultural Research Institute, New Delhi for 2016-17 and 2017-18 to study the seed deterioration in cucumber (Cucumis sativus L.) cv PusaBarkha by mimicking seed ageing with accelerated ageing. The fresh seeds were subjected to accelerated ageing at 40±1˚ C and 100% RH for a duration of 2, 4, 6 days along with control (0 days) in desiccators. With the progression of ageing, a gradual decline in the seed quality parameters, viz. seed germination and seed vigour indices was observed. The H2O2 content was within the threshold level from 0 to 4 days of ageing but beyond this, it damaged the cell membrane in seeds. Similarly, antioxidant activity (SOD, CAT, POX and higher GSH/GSSG ratio) increased initially and maintained the redox state by quenching the H2O2 effectively. Whereas, the content of H2O2 reached above the oxidative window as the activity of enzymes also decreased beyond 4 DAA. The study suggested that the H2O2 within oxidative window could be quenched efficiently; beyond this it is toxic and affects longevity as enzymes get inactivated with ageing in storage.

Seed viability and fatty acid profiles of five orchid species before and after ageing.

Changes in seed lipid composition during ageing are associated with seed viability loss in many plant species. However, due to their small seed size, this has not been previously explored in orchids. We characterized and compared the seed viability and fatty acid profiles of five orchid species before and after ageing: one tropical epiphytic orchid from Indonesia (Dendrobium strebloceras), and four temperate species from New Zealand, D. cunninghamii (epiphytic), and Gastrodia cunninghamii, Pterostylis banksii and Thelymitra nervosa (terrestrial). Seeds were aged under controlled laboratory conditions (3-month storage at 60% RH and 20 °C). Seed viability was tested before and after ageing using tetrazolium chloride staining. Fatty acid methyl esters from fresh and aged seeds were extracted through trans-esterification, and then analysed using gas chromatography-mass spectrometry. All species had high initial viability (>80%) and experienced significant viability loss after ageing. The saturated, polyunsaturated, monounsaturated and total fatty acid content decreased with ageing in all species, but this reduction was only significant for D. strebloceras, D. cunninghamii and G. cunninghamii. Our results suggest that fatty acid degradation is a typical response to ageing in orchids, albeit with species variation in magnitude, but the link between fatty acid degradation and viability was not elucidated. Pterostylis banksii exemplified this variation; it showed marked viability loss despite not having a significant reduction in its fatty acid content after ageing. More research is required to identify the effect of ageing on fatty acid composition in orchids, and its contribution to seed viability loss.

Complementary resource use in intercropped faba bean and cabbage by increased root growth and nitrogen use in organic production

AbstractIntercropping can improve yield and nitrogen use efficiency in organic vegetable production by pairing crops with complementary resource use. An intercrop field experiment was conducted to determine yield, root growth and nitrogen (N) dynamics using faba bean (Vicia faba L.) grown as a vegetable and pointed cabbage (Brassica oleracea var. capitata cv. conica). Both crops were grown in monocropping (MC) and intercropping systems (IC). Minirhizotrons were used to measure root growth. Yield of pointed cabbage per metre row was 28% higher under the IC system than under MC, whereas faba bean yield as fresh seeds did not differ. The land equivalent ratio was 1.06, showing that improved yield under IC resulted from efficient land resource use. Even though MC cabbage had the highest aboveground biomass, total N accumulation was higher under IC and MC faba bean systems. Both root frequency and intensity were greater under IC faba bean rows compared with MC faba bean because of the presence of cabbage roots in faba bean rows. Monocropped cabbage had the highest root intensity and the lowest amount of soil mineral N in the 0–1.5 m depth after harvest. Monocropped cabbage was efficient in assimilating N, whereas MC faba bean was efficient in exporting N as harvestable yield. The nitrogen use efficiency using the IC system (75%) was higher than growing faba bean (44%) and cabbage (65%) alone. Thus, faba bean as an intercrop in organic cabbage production systems improves land and N use efficiency by complementary root growth.

Conditional Seed Dormancy Helps Silene hicesiae Brullo & Signor. Overcome Stressful Mediterranean Summer Conditions.

Investigations on seed biology and ecology are of major importance for the conservation of threatened plants, both providing baseline information and suggesting practical approaches. In our study, we focused on the germination behavior of Silene hicesiae Brullo & Signor., a narrow endemic species to Panarea and Alicudi (Aeolian Archipelago, Italy), as well as one of the 50 most threatened Mediterranean island plants. Specifically, the effects of temperature, light, seed age, seed source, and collection year were evaluated; in addition, threshold temperatures and thermal–time parameters were estimated. The thermal range for fresh seed germination resulted between 5 and 15 °C, reaching up to 20 and 25 °C at increasing seed age, with 30 °C being clearly beyond the ceiling temperature. This behavior indicates that fresh seeds exhibit the Type 1 non-deep physiological dormancy, and that germination is regulated by conditional dormancy. This dormancy syndrome emerged as a highly efficient adaptation strategy for this species and, together with thermo-inhibition, would allow seeds to counteract or take advantage of Mediterranean environmental conditions. The comparison between the wild Panarea population and the corresponding ex situ cultivated progeny has enabled the identification of the latter as a suitable seed source for sustainable in situ reinforcement actions, at least in the short-term; indeed, plant cultivation for a single generation did not produce significant modifications in the germination behavior of the offspring.

Mycobiota Isolation and Aflatoxin B1 Contamination in Fresh and Stored Sesame Seeds from Rainfed and Irrigated Zones of Punjab, Pakistan

This study was carried out to evaluate the prevalence of mycobiota and aflatoxin (AF) B1 contamination in sesame seeds from rainfed and irrigated zones of the Punjab, Pakistan. For this purpose, 100 sesame seed samples were collected directly from the fields of major sesame-producing areas in rainfed and irrigated zones. The agar plate method was used for isolation of mycobiota, and thin-layer chromatography was used to determine AFB1 concentrations. Seed samples were then stored for 12 months. After 12 months, the seeds were again analyzed for mycobiota and AFB1 for comparison. All samples were positive for fungal growth under fresh and stored conditions. Twenty-one fungal species of 10 genera were isolated. Aspergillus flavus was the most prevalent contaminant found in fresh and stored sesame seeds from rainfed and irrigated zones, followed by Aspergillus niger, Alternaria alternata, and Fusarium oxysporum. The least prevalent fungi were Aspergillus ochraceus and Cladosporium oxysporum. Analysis revealed that 92% of fresh and 99% of stored seed samples were contaminated with AFB1. In the rainfed zone, 88% of fresh and 100% of stored seed samples were contaminated with AFB1, with mean concentrations of 15.74 and 33.8 ppb, respectively. In the irrigated zone, 96% of fresh and 98% of stored seed samples were contaminated with AFB1, with mean concentrations of 20.5 and 27.56 ppb, respectively. AFB1 concentrations >20 ppb were found in 20% of fresh and 100% of stored seeds samples from the rainfed zone and in 28% of fresh and 60% of stored samples from the irrigated zone and thus were not fit for human consumption as per the maximum limit (20 ppb) assigned by the U.S. Food and Drug Administration and the Food and Agriculture Organization of the United Nations. This report is the first on the mycobiota and AFB1 contamination in sesame seeds from rainfed and irrigated zones of the Punjab, Pakistan. These baseline data are an initial step in the effort to deal with this significant food safety issue.