Sheep rumen digestion and transmission of weedy Malva parviflora seeds

2006 ◽  
Vol 46 (10) ◽  
pp. 1251 ◽  
Author(s):  
P. J. Michael ◽  
K. J. Steadman ◽  
J. A. Plummer ◽  
P. Vercoe

The effect of sheep digestion and mastication on Malva parviflora L. seed transmission, viability and germination was investigated. Mature M. parviflora seeds were subjected to 2 seed treatments: ‘scarified’, where the hard seed coat was manually cut to allow imbibition, and ‘unscarified’, where the hard seed coat was not cut. Seeds were placed directly into the rumen of fistulated sheep and removed at 0, 12, 24, 36 and 48 h of rumen digestion. After 12 h of in sacco exposure to digestion in the rumen, the germination of seeds that were initially scarified dropped from 99.2 to 1.4% and longer exposure periods produced no germinable seeds. In contrast, seeds that were unscarified when placed in the rumen produced over 92% germination regardless of in sacco digestion time, although manual scarification after retrieval was essential to elicit germination. In a second experiment, unscarified seeds (29 000) were fed in a single meal to fistulated sheep and feces were collected at regular intervals between 6 and 120 h after feeding. Fecal subsamples were taken to determine number of seeds excreted, seed germination on agar and seed germination from feces. Major seed excretion in the feces commenced after 12 h and continued until 144 h, with peaks between 36 and 72 h after consumption. Although mastication and gut passage killed the majority of unscarified seeds, about 20% were recovered intact and over 90% of these recovered seeds were viable and could, thus, potentially form an extensive seed bank. A few excreted seeds (1%) were able to germinate directly from feces, which increased to a maximum of 10% after subsequent dry summer storage (3 months). Through information gained in this study, there is a potential to utilise livestock in an integrated weed management program for the control of M. parviflora, provided additional measures of weed control are in place such as holding periods (>7 days) for movement of livestock from weed infested areas.

2020 ◽  
Vol 100 (6) ◽  
pp. 666-673
Author(s):  
Yunpeng Gao ◽  
Mingwei Zhu ◽  
Qiuyue Ma ◽  
Shuxian Li

The seeds of Cercis chinensis Bunge are important for reproduction and propagation, but strong dormancy controls their germination. To elucidate the causes of seed dormancy in C. chinensis, we investigated the permeability of the hard seed coat and the contribution of the endosperm to physical dormancy, and we examined the effect of extracts from the seed coat and endosperm. In addition, the effectiveness of scarification methods to break seed dormancy was compared. Cercis chinensis seeds exhibited physical and physiological dormancy. The hard seed coat played an important role in limiting water uptake, and the endosperm acted as a physical barrier that restricted embryo development in imbibed seeds. Germination percentage of Chinese cabbage [Brassica rapa subsp. chinensis (L.) Hanelt] seeds was reduced from 98% (control) to 28.3% and 56.7% with a seed-coat extract and an endosperm extract, respectively. This demonstrated that both the seed coat and endosperm contained endogenous inhibitors, but the seed-coat extract resulted in stronger inhibition. Mechanical scarification, thermal scarification, and chemical scarification had positive effects on C. chinensis seed germination. Soaking non-scarified seeds in gibberellic acid (GA3) solution did not promote germination; however, treatment with exogenous GA3 following scarification significantly improved germination. The optimal method for promoting C. chinensis seed germination was soaking scarified seeds in 500 mg·L−1 GA3 for 24 h followed by cold stratification at 5 °C for 2 mo.


2020 ◽  
Vol 30 (1) ◽  
pp. 33-45
Author(s):  
Rabbi Hoque ◽  
Rita Sarah Borna ◽  
M Imdadul Hoque ◽  
RH Sarker

Poor seed germination is the main obstacle for seed propagation of Rauwolfia tetraphylla L. in nature. The high viability (83.1%) of seeds in nature and the presence of viable embryo indicate that viability is not the only reason behind poor seed germination of this valuable medicinal plant. However, to overcome the problem of poor seed propagation, an efficient protocol has been developed for R. tetraphylla. Among the various treatments the maximum rate of ex vitro seed germination (13.33%) was found when the seeds were treated with 100 ppm of GA3. Response of in vitro germination was found to vary under different conditions. Not only that the rate was much higher compared to ex vitro germination. The rate of seed germination was found to be 78% in MS without PGR (plant growth regulator) supplements, while it was 70 and 78% in cotton bed under light and dark, respectively. It was 80% in incubator at 37ºC. In R. tetraphylla the hard seed coat is regarded as one of the barriers for germination and it can be easily eliminated by removing the hard seed coat. In vitro raised plantlets were reared in nature following proper acclimatization where they produced flowers as well as seeds. Apart from the said investigation, a method for in vitro shoot formation was also developed. Best response (90.7%) towards in vitro shoot regeneration was obtained from nodal segment when they were cultured on MS supplemented with 2.2 mg/l BA and 0.1 mg/l NAA. It took about 10-12 days to initiate shoots. About 9.9 ± 0.87 shoots were obtained per explants and their length was recorded as 2.28 ± 0.21 cm after six weeks. Various concentrations of IBA and NAA were used for in vitro root induction, but the in vitro raised shoots did not produce roots. Plant Tissue Cult. & Biotech. 30(1): 33-45, 2020 (June)


Weed Science ◽  
2016 ◽  
Vol 65 (1) ◽  
pp. 141-150 ◽  
Author(s):  
Wei Tang ◽  
Jie Chen ◽  
Jianping Zhang ◽  
Yongliang Lu

Triquetrous murdannia is an annual weed commonly found in rice fields in China. Laboratory and screenhouse experiments were carried out to determine the effect of light, temperature, osmotic and salt stress, seed burial depth, amount of rice residue, and depth of flooding on seed germination and seedling emergence of triquetrous murdannia and to evaluate the response of this weed to commonly available POST herbicides in China. Germination was greater than 93% under a wide day/night temperature range of 20/10 to 30/20 C in the light/dark regime. The time to onset of germination decreased as temperature increased. Germination was slightly stimulated when seeds were placed in light/dark conditions compared with seeds placed in the dark. The osmotic potential and NaCl concentration required for 50% inhibition of maximum germination were −0.5 MPa and 122 mM, respectively. The highest germination (68%) was observed from seeds sown on the soil surface, but decreased with increasing burial depth. Only 7% of seedlings emerged from a depth of 4 cm, and no seedlings emerged from seeds buried deeper than 6 cm. Seedling emergence decreased from 93 to 35% with increasing quantity of rice residue (1 to 6 103kg ha−1) applied on the soil surface. Seedling emergence was reduced by 40, 48, 64, and 70% at flooding depths of 1, 2, 4, and 6 cm, respectively, for the seeds sown on the soil surface. Fluroxypyr and MCPA herbicides provided 100% control of triquetrous murdannia at the 2- to 6-leaf stages; however, to achieve 100% control with bispyribac-sodium, MCPA+bentazone or MCPA+fluroxypyr, herbicides had to be applied by the 4-leaf stage. The results of this study could help in developing more sustainable and effective integrated weed management strategies for the control of triquetrous murdannia in rice fields in China.


2004 ◽  
Vol 18 (3) ◽  
pp. 648-657 ◽  
Author(s):  
Hilary A. Sandler ◽  
Joanne Mason ◽  
Wesley R. Autio ◽  
Thomas A. Bewick

To address grower concerns that repeated use of dichlobenil could negatively affect cranberry productivity, field studies were conducted at two commercial farms in either high weed density (HW) or low weed density (LW) areas. Data from 4 yr of repeat annual applications of 0, 1.8, and 4.5 kg ai/ha dichlobenil indicated minimal negative impact on cranberry vines. Herbicide application did not affect upright productivity, leaf biomass production, percent fruit set, or other yield parameters adversely; in addition, no improvement in these parameters was noted. Although the interaction of herbicide application with weed density on cranberry root length varied with sampling date, no consistent trend (adverse or positive) was seen. The presence of weeds, rather than herbicide application, was the important determinant of yield. Vines in LW areas produced more marketable fruit and had higher percentage of fruit set than vines growing in HW areas. Repeat annual applications of dichlobenil on commercial cranberry beds may be considered as part of a viable integrated weed management program with no adverse effect on crop growth or yield.


2015 ◽  
Vol 29 (3) ◽  
pp. 509-518 ◽  
Author(s):  
William S. Curran ◽  
John M. Wallace ◽  
Steven Mirsky ◽  
Benjamin Crockett

A field experiment was conducted in 2009–2010 at Pennsylvania and Maryland locations, and repeated it in 2010–2011 to test the effectiveness of POST-applied herbicides at fall and spring timings on seeded hairy vetch in winter wheat. A total of 16 herbicide treatment combinations was tested that included synthetic auxins, acetolactate synthase (ALS) inhibitors, and a protoporphyrinogen oxidase inhibitor. Spring applications tended to be more effective than fall applications. Among synthetic auxins, clopyralid (105 g ae ha−1) and treatments containing dicamba (140 g ae ha−1) were effective at both timings, resulting in greater than 90% hairy vetch control at wheat harvest. Pyroxsulam and prosulfuron applied at 18 g ai ha−1 provided the most effective hairy vetch control (> 90%) at both application timings among ALS inhibitors. Spring applications of several herbicides provided moderate (> 80%) to high (> 90%) levels of hairy vetch control, including: 2,4-D amine (140 g ae ha−1), mesosulfuron-methyl (15 g ai ha−1), tribenuron-methyl (13 g ai ha−1), and thifensulfuron/tribenuron-methyl treatments (16 and 32 g ai ha−1). Winter wheat injury was evaluated, but symptoms were negligible for most treatments. Winter wheat yields declined with increasing hairy vetch biomass. Fall herbicides may be prioritized to reduce hairy vetch competition during the fall and early spring growing season. Our research has established that several synthetic auxin and ALS-inhibiting herbicides, applied POST in fall or spring, can be safely used in winter wheat to control hairy vetch in an integrated weed management program.


1987 ◽  
Vol 17 (4) ◽  
pp. 294-298 ◽  
Author(s):  
R. J. Hoff

The inner layer of the seed coat, a papery membrane, and physiological conditions of the gametophyte–embryo were shown to be major sites of dormancy in seed of western white pine. The hard seed coat layer was a minor site. With no stratification, 7% of the seeds were not dormant, 9% were dormant because of the hard seed coat, 34% were dormant because of the inner seed coat, and 50% were dormant because of physiological conditions of the gametophyte–embryo. These values varied with stratification times and seed lots (families).


2016 ◽  
Vol 44 (2) ◽  
pp. 111
Author(s):  
Usman , ◽  
Bambang Sapta Purwoko ◽  
Muhamad Syukur ◽  
Dan Dwi Guntoro

<em>ABSTRACT<br /><br />Barnyard grass (Echinochloa crus-galli (L.) P. Beauv.) is a major weed competitor to rice production in Indonesia. In order to develop integrated weed management program, a research to select competitive rice lines to E. crus-galli was conducted in a green house of Indonesian Centre of Agricultural Biotechnology and Genetic Resource Research and Development Bogor. The research design was split plot with four replications, E. crus-galli was designed as the main plot (rice without E. crus-galli compared  rice with four E. crus-galli per pot), and the sub-plots were 25 genotypes (23 lines, 1 tolerant variety and 1 sensitive variety). Level of tolerance was determined by the reduction percentage of grains weight, the number of productive tillers and dry matter weight. The results showed that rice competition with E. crus-galli reduced plant height, productive tiller numbers, filled spikelet numbers per panicle, dry matter weight and dry grain weight. Three lines, i.e., IR10L-155, IR10L-133 and BIO-R84-1 were classified as tolerant, 19 lines were moderate and 3 lines were sensitive to E. crus-galli competition.<br /><br />Keywords: Barnyard grass, competition, sensitive line, yield reduction </em>


2021 ◽  
Vol 17 (2) ◽  
pp. 509-514
Author(s):  
A. Krishna ◽  
Jitendra Kumar S. Hilli

Soapnut (Sapinduas emarginatus) is one of the most primitive precious useful plants since ancient times. This plant was domesticated due to its multifarious usefulness. The study was conducted in College of Forestry, Sirsi during 2019-20 to know the influence of post scarification storage treatments on seed germination and quality in Sapinduas emarginatus. The seeds were collected from in and around Sirsi area. In soap nut, the basic problem is poor seed germination due to hard seed coat. The seeds were treated with concentrated H2So4 for 12min and stored under laboratory condition for six months. At monthly interval, seed samples were drawn and evaluated for post scarification germination. The germination behaviour remarkably influenced due to scarification and without scarification during experimentation. The untreated seeds recorded the maximum germination (68%) compared to scarified seeds (22.85%).Speed of germination was highest in seed without scarification treatment (2.7) compared to scarified seeds. Mean daily germination was highest in without scarified seeds (1.04) and lowest in the scarified seeds (0.32). Peak value was maximum in without scarified seeds (0.50) compared to scarified seeds (0.22). Seedling vigour index was significantly highest in without scarified seeds (1290) compared to scarified seeds (455). In general, scarified seeds with conc. H2SO4 for 12 min affected seed germination due high conc. H2SO4 because of chemical residues remaining in seed that affects the embryo. As the advancement in storage period the seed coat may lose the integrity so, germination was improved in without scarified seeds.


1999 ◽  
Vol 124 (4) ◽  
pp. 430-432 ◽  
Author(s):  
John R. Duval ◽  
D. Scott NeSmith

Production of triploid watermelon [Citrullus lanatus (Thunb.) Matsum & Nakai] transplants is hindered by poor, inconsistent emergence, and frequent seed coat adherence to cotyledons. Seed coat adherence leads to weakened and slow growing plants. High seed costs, coupled with stand establishment problems, discourages transplant producers from growing this crop. Improvement of triploid watermelon emergence will lessen financial risks to growers and transplant producers and will provide a more reliable production system. Mechanical scarification was evaluated as a means to overcome inconsistent emergence and seed coat adherence. Seeds of `Genesis' triploid watermelon were placed in a cylinder with 100 g of very coarse sand (1.0 to 2.0 mm diameter) and rotated at 60 rpm for 0, 6, 12, 24, and 48 hours in a series of experiments. Number of emerged seed was recorded daily, to obtain emergence dynamics. No significant differences were observed in seed coat adherence among treatments. The longest duration of scarification However, enhanced emergence as compared to the control in three of four experiments. These data support earlier suggestions that a thick or hard seed coat is a factor contributing to poor germination and emergence of triploid watermelons.


2019 ◽  
Vol 41 (3) ◽  
pp. 318-327
Author(s):  
Rosemeire Carvalho da Silva ◽  
Andreza Cerioni Belniaki ◽  
Elisa Serra Negra Vieira ◽  
Francine Lorena Cuquel ◽  
Maristela Panobianco

Abstract: Calophyllum brasiliense Cambess. (guanandi) is a native species with medicinal potential and also generates expectation for commercial use (wood) and for recovery of degraded areas. These seeds have physical and mechanical dormancy, requiring techniques for dormancy release; knowledge of seed and seedling morphology that assists laboratory analysis and propagation of the species is also necessary. The objective of this study was to describe the morphological structures of the seeds and normal and abnormal seedlings of guanandi, and also investigate if complete extraction of the endocarp and the seed coat to overcome dormancy will affect the morphology and initial plant development, and consequently production of transplants. Guanandi seeds are large (1000 seed weight of 1480.9 g) with a hard seed coat; cotyledons account for most of the embryo and serve as a reserve; the embryonic axis is small (1.0-2.0 mm) in relation to the seed, yet it is differentiated. The seedlings have hypogeal cryptocotylar germination, with cotyledonary petioles, taproot, and epicotyl developing into a long stem and a tip protected by cataphylls. The main abnormalities in seedlings are related to the root system. Extraction of the endocarp and seed coat does not alter the morphology of seedlings and promotes their greater development, which may be an advantageous strategy.


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