Impact of Biochar Application on Germination Behavior and Early Growth of Maize Seedlings: Insights from a Growth Room Experiment

Reduced germination and early crop maturity due to soil compaction, nutrients stress, and low moisture are major constraints to achieve optimum crop yield, ultimately resulting in significant economic damages and food shortages. Biochar, having the potential to improve physical and chemical properties of soil, can also improve nutrients and moisture access to plants. In the present study, a growth room experiment was conducted to assess biochar influence on maize seed germination, early growth of seedlings, and its physiological attributes. Corn cob biochar (CCB) was mixed with soil at different rates (0.5%, 1%, 1.5%, 2%, 2.5%, and 3% w/w) before seed sowing. Results obtained showed that increasing CCB application rate have neutral to positive effects on seed germination and seedling growth of maize. Biochar addition at the rate of 1.5% (w/w) significantly increased shoot dry biomass (40%), root dry biomass (32%), total chlorophyll content (a and b) (55%), germination percentage (13%), seedling vigor (85%), and relative water content (RWC) (68%), in comparison to un-amended control treatment. In addition to this, it also improved germination rate (GR) by 3% as compared to control treatment, while causing a reduction in mean emergence time (MET). Moreover, application of biochar (3%) also resulted in enhancement of antioxidant enzyme activity, particularly superoxide dismutase (SOD) and catalase (CAT) by 13% and 17%, respectively. Conclusively, biochar application is an attractive approach to improve the initial phase of plant growth and provide better crop stand and essential sustainable high yields.

Storage of proliferating gooseberry cultures under slow growth conditions

Short storage of in vitro cultures under slow-growth conditions is included in the commercial large-scale micropropagation process. It is dictated by the organizational scheme that provides temporary stop multiplication of shoots for some months. To avoid subculturing to fresh media every 4 weeks, which is obligatory for gooseberry, they can be kept in conditions that protect them from ageing, by slowing down their metabolism. To develop a rational schedule of gooseberry micropropagation, two experiments were used to adopt a temperature and length of time for storage. The best results were obtained with storage conditions at 2 °C for two or four months for proliferating cultures. Under these conditions, the percentage of necrotic shoots was low (< 10%), and shoot proliferation in the subsequent passages was at a level similar to proliferation cultures incubated in the growth room and sub-cultured monthly. The rate of shoots > 1 cm was higher than in the control in the growth room. Storage at 4 °C increased the probability of necrotic shoots up to 80% and decreased the number of all shoots and shoots > 1 cm in subsequent passages.

Host suitability of different common bean varieties in a growth room to the plant-parasitic nematodes Pratylenchus thornei and P. neglectus

Summary Pratylenchus thornei and P. neglectus attack common bean and cause economic yield losses throughout cultivated areas in Turkey. The most effective management strategy for the P. thornei and P. neglectus infections is crop rotation with non-host crops and breeding resistant/tolerant varieties. However, parent bean genotypes immune to P. thornei and P. neglectus are not available for breeding programmes; thus, resistant varieties are commonly incorporated as parents. In the present research, a total of 36 common bean varieties were tested in a growth room for their host response to these two nematode pests. The reproduction factor and the population density of both nematode species were calculated. All tested bean varieties showed varying levels of resistance and susceptibility to P. thornei and P. neglectus. Among the dry bean varieties, nine were found to be resistant to P. thornei and three to P. neglectus, with three varieties (‘Kantar-05’, ‘Önceler-98’ and ‘Karacasehir-90’) resistant to both species. Among fresh bean varieties, ten were found to be resistant to P. thornei and four to P. neglectus, with four varieties (‘Helda’, ‘Gina’, ‘Gelincik’ and ‘Bourgondia’) resistant to both species. The resistant common bean varieties identified in this study are a valuable untapped genetic pool that will offer improved resistance levels to P. thornei and P. neglectus, especially ‘Gina’ and ‘Önceler-98’, which seem to possess a great source of resistance to P. thornei and P. neglectus, respectively, and can be used in breeding programmes in the near future.

SEED DORMANCY BREAKING OF AN ENDANGERED MEDICINAL TREE SPECIES (TAXUS BACCATA L.) USING EMBRYO CULTURE

Natural regeneration of Taxus baccata L. is constrained due to the depth of seed dormancy requirements (often taking two or more years) and low seed germination. Further, the conventional method of vegetative propagation by cuttings is associated with difficulties in rooting. Hence, for the first time, this study describes an efficient and reproducible in vitro protocol for breaking the dormancy of seeds from the endangered forest tree T. baccata L. via zygotic embryo culture. Embryos isolated from 100% sterile seeds were cultured on DCR medium that contains sucrose (30 g/l), agar (8 g/l), and activated charcoal (5 g/l), fortified with different concentrations of Plant Growth Regulators (PGRs), and held at a temperature of 25 ± 2 ºC in a growth room. The results revealed that the in vitro embryo germination percentage was mostly affected by gibberellic acid (GA3) and thidiazuron (TDZ). Among the nine treatments, the treatments with 0.5 mg/l TDZ and 1 mg/l GA3 showed the highest germination (100%), while the other treatments all increased the germination percentages significantly compared to the control (37.5%). The 1/2 DCR medium with the addition of 0.1 mg/l indole-3-butyric acid (IBA) resulted in the highest rooting ratio (94%). However, the greatest root and hypocotyl elongation (59.37 ± 3.77 and 62.75 ± 4.43 mm, respectively) occurred when seedlings were cultured on 1/2 DCR medium containing 0.5 mg/l BA. Plantlets were transplanted into plastic pots containing an autoclaved garden soil, sand, and vermiculite mixture (1:1:1) and held at a temperature of 25 ± 2 ºC in a growth room for 4 weeks before being transplanted into the greenhouse. These results indicated that the protocol developed during the current study will be useful to overcome seed dormancy and for multiplication and conservation of the species T. baccata L.

Aromatik Tıbbi Bitki olan Mentha x piperita L. ve Mentha pulegium L.’nin in vitro Kallus İndüksiyonu ve Mikroçoğaltım yoluyla Geliştirilmesi

In this study, we evaluate the potential for in vitro propagation of Mentha spp. for mass production. The two Mentha spp. (Mentha x piperita L., M. pulegium L.) were propagated with four successive 60-day subcultures in MS medium supplemented with for 100µL/L NAA (Naphthylacetic Acid) and 600µl/L IBA( Indole Butyric Acid). The shoots were rooted in the same media. The rooted plantlets were finally acclimatized in a growth room. Callus induction was carried out in MS (Murashige and Skoog) media supplemented with 100µL/L NAA and 250µL/L BAP (Benzylaminopurine). Callus was successfully induced from nodes of Mentha pulegium L. Through micropropagation, both Mentha spp increased in multiplication rates around 6-fold per month compared to the traditional propagation method. Mentha x piperita and Mentha pulegium showed the most significant potential for plantlet production through the micropropagation method.

Light sources on the germination and initial in vitro establishment of Schomburgkia crispa Lindl., a species of the Brazilian Cerrado

ABSTRACT: Light is one of the factors that influence the germination and initial establishment of orchids under in vitro cultivation. This study evaluated the effect of different light sources on these stages in in vitro cultivation of Schomburgkia crispa Lindl. After sowing in an aseptic environment, we stored the cultures in a screened greenhouse (natural light) or in a growth room with the following light sources: 3,000 K yellow LED; 6,500 K white LED [1]; 6,500 K white LED [2]; or 6,500 K white fluorescent lamp (control). We assessed germination percentage and initial seedling establishment at 45 and 90 days after sowing. Light did not influence the germination of S. crispa. However, the use of 3,000 K LED provided a faster initial establishment of S. crispa when compared to the other light sources, also presenting lower seedling mortality. Thus, the light source 3,000 K LED is a potential substitute for the 6,500 K fluorescent lamps and LEDs used in growth rooms in in vitro culture laboratories.

Targeting Cytokinin Homeostasis in Rapid Cycling Brassica rapa with Plant Growth Regulators INCYDE and TD-K

Modifying the cytokinin content in plants is a means of improving plant productivity. Here, we report the development and biological activity of compound TD-K (1-(furan-2-ylmethyl)-3-(1,2,3-thiadiazol-5-yl)urea)which is related to thidiazuron. TD-K—which exhibited extremely high antisenescence activity in the wheat leaf bioassay—and INCYDE (2-chloro-6-(3-methoxyphenyl)aminopurine)—a plant growth regulator reported to inhibit cytokinin oxidase/dehydrogenase (CKX), an enzyme involved in the degradation of the plant hormone cytokinin—were selected for investigation of their effects on the model plant Rapid Cycling Brassica rapa (RCBr). We monitored the expression of BrCKX and isopentenyl transferase (BrIPT), which codes for the key cytokinin biosynthesis enzyme, in developing leaves following INCYDE and TD-K application. Growth room experiments revealed that INCYDE increased RCBr seed yield per plant, but only when applied multiple times and when grown in 5 mM KNO3. Expression in control leaves showed transient, high levels of expression of BrCKX and BrIPT at true leaf appearance. Following INCYDE application, there was a rapid and strong upregulation of BrCKX3, and a transient downregulation of BrIPT1 and BrIPT3. Interestingly, the upregulation of BrCKX3 persisted in a milder form throughout the course of the experiment (16 days). TD-K also upregulated BrCKX3. However, in contrast to INCYDE, this effect disappeared after two days. These results suggest that both compounds (CKX inhibitor and cytokinin TD-K) influenced cytokinin homeostasis in RCBr leaves, but with different mechanisms.

Micro propagation of Adiantum Capillus plant through a culture of plant spores

This experiment was conducted in Biotechnology research center BTRC for the purpose of studying the possibility of propagate Adiantum Capillus plant by using spores through plant tissues culture technology, which is one of the endangered plants in Libya. MS media was used in this study supplemented with some growth regulators (cytokines) of benzyl adenine BA and Kinten K at different concentrations (0.0, 0.5, 1.0, 2.0) mg / l. The results indicate that the growth of spores represented by the increase in the length and size of the vegetative masses in the MS nutritional medium equipped with BA growth regulator at a concentration of 2.0 mg / l is significantly higher than other treatments. The obtained plants were adapted by using growth medium of the Betmos and sand mixture in a ratio of 1: 2 in the growth room. The branches and roots formed when the plant moved to the greenhouse in the same medium of development

Seed treatment of canola (Brassica napus) with the endomycorrhizal fungus Piriformospora indica does not reduce clubroot

A Basidiomycete endomycorrhizal fungus, Piriformospora indica, colonizes and promotes the growth of canola and other Brassica crops, and can reduce diseases of other crops. Clubroot is an important disease of Bbrassica crops caused by the obligate, soil-borne pathogen Plasmodiophora brassicae. The effect of P. indica on clubroot severity in canola was assessed in replicated growth room studies. Seed was treated with P. indica using a proprietary process. Microscopic observation confirmed that canola roots grown from treated seed were colonized by P. indica. However, P. indica did not consistently reduce clubroot severity and did not promote the growth of canola.