Vigor Parameters Research Articles

Impact of fertilizer priming on seed germination behavior and vigor of maize

Laboratory experiments were conducted to examine the efficacy of fertilizer priming on seed germination behavior and vigor of two maize cultivars “Azam and Phari” at Agronomy Research Laboratory, University of Agriculture, Peshawar- Pakistan during 2015. Studied treatments include hydropriming (distilled water) and osmopriming with Calcium Ammonium Nitrate (CAN) at 0.5% for 24 hours. Non primed seed were used as control. Data were recorded on germination and vigor parameters according to standard procedures. Results showed that both hydro and osmo-priming significantly improved germination %, mean germination time, germination index, plumule and radical length, seedling fresh and dry weight of both cultivars as compared to control treatment. Cultivar Azam performed better in all germination and vigor attributes than Phari. It was concluded that both hydro and osmopriming with Calcium Ammonium Nitrate (CAN) at 0.5% for 24 hours are practical approaches for improving growth and vigor of maize crop under harsh environment.

Time series analysis of co-polarization phase difference (PPD) for winter field crops using polarimetric C-band SAR data

ABSTRACTThe utility of time series polarimetric C-band data for vegetation state monitoring was explored to understand the mechanism of growth and phenology for important winter crops in India. Parameters investigated were HH–VV phase difference (co-polarization phase difference, PPD), amplitude ratio, and polarization indices. Data were acquired during the entire growth phase categorized as early, mid/peak vegetative, and post-vegetative /flowering phase. The trend emerging in this study showed a shift in the phase difference distribution for agricultural areas relating to the growth rate for various crops. The time series data set revealed that the PPD is a function of frequency and was directly affected by crop type (planophile or erectophile), vigour, structure, and crop biophysical parameters, particularly biomass. The behaviour of crop biomass with PPD responded differentially across crop architectures and vigour classes. Co-polarization index was found to be a good measure for discrimination in early growth stages while cross-polarization index suited in advanced vegetative stages where geometrical orientation was uniform. The PPD captured the change in frequency distribution resulting in a peaked distribution at sowing changing to smooth, well-spread frequency distribution as the peak vegetation stage approaches. This histogram nature is observed to be gradual for high-biomass crops and peaked in case of the low-biomass crops. It is indicative of the rate of growth; a low peaked normal curve indicates faster growth rate and resulting in high biomass. The amplitude ratio in the later phase of growth as on the third date is similarly altered as in the VV returns from the crop. Intuition of the rate of growth and plant vigour is obtained from the temporal PPD pattern. The current study shows that while phase differences and amplitude ratio carry little information content on a single resolution cell basis, their spatial distribution over a wider time span can be used to derive quantitative relationships between SAR response and crop condition. The synergy of information involving the above parameters were used to derive useful information on the vegetation.

THE COMBINATION OF UAV SURVEY AND LANDSAT IMAGERY FOR MONITORING OF CROP VIGOR IN PRECISION AGRICULTURE

Abstract. Mapping of the with-in field variability of crop vigor has a long tradition with a success rate ranging from medium to high depending on the local conditions of the study. Information about the development of agronomical relevant crop parameters, such as above-ground biomass and crop nutritional status, provides high reliability for yield estimation and recommendation for variable rate application of fertilizers. The aim of this study was to utilize unmanned and satellite multispectral imaging for estimation of basic crop parameters during the growing season. The experimental part of work was carried out in 2014 at the winter wheat field with an area of 69 ha located in the South Moravia region of the Czech Republic. An UAV imaging was done in April 2014 using Sensefly eBee, which was equipped by visible and near infrared (red edge) multispectral cameras. For ground truth calibration the spectral signatures were measured on 20 sites using portable spectroradiometer ASD Handheld 2 and simultaneously plant samples were taken at BBCH 32 (April 2014) and BBCH 59 (Mai 2014) for estimation of above-ground biomass and nitrogen content. The UAV survey was later extended by selected cloud-free Landsat 8 OLI satellite imagery, downloaded from USGS web application Earth Explorer. After standard pre-processing procedures, a set of vegetation indices was calculated from remotely and ground sensed data. As the next step, a correlation analysis was computed among crop vigor parameters and vegetation indices. Both, amount of above-ground biomass and nitrogen content were highly correlated (r > 0.85) with ground spectrometric measurement by ASD Handheld 2 in BBCH 32, especially for narrow band vegetation indices (e.g. Red Edge Inflection Point). UAV and Landsat broadband vegetation indices varied in range of r = 0.5 – 0.7, highest values of the correlation coefficients were obtained for crop biomass by using GNDVI. In all cases results from BBCH 59 vegetation stage showed lower relationship to vegetation indices. Total amount of aboveground biomass was identified as the most important factor influencing the values of vegetation indices. Based on the results can be assumed that UAV and satellite monitoring provide reliable information about crop parameters for site specific crop management. The main difference of their utilization is coming from their specification and technical limits. Satellite survey can be used for periodic monitoring of crops as the indicator of their spatial heterogeneity within fields, but with low resolution (30 m per pixel for OLI). On the other hand UAV represents a special campaign aimed on the mapping of high-detailed spatial inputs for site specific crop management and variable rate application of fertilizers.

THE COMBINATION OF UAV SURVEY AND LANDSAT IMAGERY FOR MONITORING OF CROP VIGOR IN PRECISION AGRICULTURE

Mapping of the with-in field variability of crop vigor has a long tradition with a success rate ranging from medium to high depending on the local conditions of the study. Information about the development of agronomical relevant crop parameters, such as above-ground biomass and crop nutritional status, provides high reliability for yield estimation and recommendation for variable rate application of fertilizers. The aim of this study was to utilize unmanned and satellite multispectral imaging for estimation of basic crop parameters during the growing season. The experimental part of work was carried out in 2014 at the winter wheat field with an area of 69 ha located in the South Moravia region of the Czech Republic. An UAV imaging was done in April 2014 using Sensefly eBee, which was equipped by visible and near infrared (red edge) multispectral cameras. For ground truth calibration the spectral signatures were measured on 20 sites using portable spectroradiometer ASD Handheld 2 and simultaneously plant samples were taken at BBCH 32 (April 2014) and BBCH 59 (Mai 2014) for estimation of above-ground biomass and nitrogen content. The UAV survey was later extended by selected cloud-free Landsat 8 OLI satellite imagery, downloaded from USGS web application Earth Explorer. After standard pre-processing procedures, a set of vegetation indices was calculated from remotely and ground sensed data. As the next step, a correlation analysis was computed among crop vigor parameters and vegetation indices. Both, amount of above-ground biomass and nitrogen content were highly correlated (r > 0.85) with ground spectrometric measurement by ASD Handheld 2 in BBCH 32, especially for narrow band vegetation indices (e.g. Red Edge Inflection Point). UAV and Landsat broadband vegetation indices varied in range of r = 0.5 – 0.7, highest values of the correlation coefficients were obtained for crop biomass by using GNDVI. In all cases results from BBCH 59 vegetation stage showed lower relationship to vegetation indices. Total amount of aboveground biomass was identified as the most important factor influencing the values of vegetation indices. Based on the results can be assumed that UAV and satellite monitoring provide reliable information about crop parameters for site specific crop management. The main difference of their utilization is coming from their specification and technical limits. Satellite survey can be used for periodic monitoring of crops as the indicator of their spatial heterogeneity within fields, but with low resolution (30 m per pixel for OLI). On the other hand UAV represents a special campaign aimed on the mapping of high-detailed spatial inputs for site specific crop management and variable rate application of fertilizers.

Effect of Proline and Salicylic Acid on Seed Vigour Parameters in Fresh and Aged Seeds of Radish (Raphanus sativusL.)

In the present investigation, fresh and aged seeds of radish were treated with salicylic acid using 50 mg/L and 100 mg/L and proline 5mM and 10 mM concentrations of each for 12 hr and 24 hr with the objective to enhance the germination and seed vigour of aged seeds. In general aged seeds showed less germination as compared to fresh seeds. All the seed treatments increased the germination percentage and seed vigour I and II in both fresh and aged seeds as compared to control and the effect was maximum when treated with proline 10 mM.

Seed viability and vigour in naturally aged seeds of coriander (Coriandrum sativum)

In the present investigation, three seed lots of eight varieties/genotypes, viz. DH 224, DH 226, DH 242, DH 259, DH 294, DH 296 (advance genotypes) and DH 228 (Hisar Bhoomit) and Hisar Anand (released varieties) of coriander were subjected to study the effect of natural ageing on different seed quality parameters. All the seed lots were analyzed for standard germination test (%), root length (cm), shoot length (cm), seedling dry weight (mg), seedling vigour index-I, seedling vigour index-II, accelerated ageing test (%), electrical conductivity (mS/cm/seed) of seed leachates, seed density (g/cc), dehydrogenase activity test (OD/g/mL), field emergence index and field establishment (%). Results revealed that all the varieties/genotypes showed the germination percentage above the Minimum Seed Certification Standards (60%) in Lot-A (½ year old seed) and Lot-B (1½ years old seed). Standard germination (%), seedling length (cm), seedling dry weight (mg), seedling vigour index-I &II, accelerated ageing test (%), dehydrogenase activity test (OD/g/mL), field emergence index and field establishment (%) decreased significantly and progressively as the ageing period increased. The electrical conductivity was negatively and significantly correlated with all seed viability and vigour parameters. Results also revealed that viability and vigour of seeds declined with faster rate in Lot-C (2½ years old seed). Among all the varieties/genotypes, genotypes DH 224 and DH 228 were found most promising for various parameters of viability and vigour.

Grafting, Scion and Rootstock Effects on Survival Rate, Vegetative Growth and Fruit Yield of High Tunnel-grown Grafted Pepper (Capsicum annuum L.) Plants

The objective of this study was to develop information useful to pepper (Capsicum annuum L.) rootstock breeders, grafted plant propagators and growers managing commercial plantings in semi-protected settings. To accomplish this, an experiment involving four phenotypically diverse scion cultivars and five rootstocks grafted in all combinations along with self-grafted and non-grafted cultivars as controls was completed twice. The effects of the grafting process, scion cultivars and rootstock genotypes on grafted plant performance were delineated by measures of post-grafting plant survival (%), plant vegetative vigor and by early and total season yield parameters. The grafting process significantly increased vegetative vigor parameters, most notably in 2014 whereas the yield parameters of self-grafted plants exceeded their non-grafted counterparts only in 2015. In both years, scion performance in graft combinations remained characteristic of the cultivar type; long-fruited cultivars ‘Eigman’ and ‘Kurtovszka Kapia’ had lower survival rates, generally exhibited greater vegetative vigor, and amassed greater yields per m2 than blocky-fruited ‘Toronto’ and ‘Zedinca’. In general, graft combinations using commercial pepper rootstocks 52-03 RZ and Tan Tan (No: 12G076) outperformed those composed of standard cultivars or breeding lines used as rootstocks. Scions on these rootstocks exhibited greater vegetative vigor in both years and higher yields per m2 than non-grafted controls in 2014. The superior performance of 52-03 RZ and Tan Tan (No: 12G076) in this study exemplified the advantage of using rootstocks specifically bred for optimum root system performance and compatibility with a variety of scions. However, significant scion × rootstock interactions and seasonal differences in performance suggested, that as new rootstocks are developed or as new graft combinations are introduced, it will be necessary to rigorously test them in multiple environments to insure commercial success.

To die or not to die: early warnings of tree dieback in response to a severe drought

Summary Some disturbances can drive ecological systems to abrupt shifts between alternative stages (tipping points) when critical transitions occur. Drought‐induced tree death can be considered as a nonlinear shift in tree vigour and growth. However, at what point do trees become predisposed to drought‐related dieback and which factors determine this (tipping) point? We investigated these questions by characterizing the responses of three tree species, silver fir (Abies alba), Scots pine (Pinus sylvestris) and Aleppo pine (Pinus halepensis), to a severe drought event. We compared basal area increment (BAI) trends and responses to climate and drought in declining (very defoliated and dying) vs. non‐declining (slightly or not defoliated) trees by using generalized additive mixed models. Defoliation, BAI and sapwood production were related to functional proxies of tree vigour measured at the onset and end of the drought (non‐structural carbohydrate concentrations, needle N content and C isotopic discrimination, presence of wood‐inhabiting fungi). We evaluated whether early warning signals (increases in synchronicity among trees or in autocorrelation and standard deviation) could be extracted from the BAI series prior to tree death. Declining silver fir and Scots pine trees showed less growth than non‐declining trees one to three decades, respectively, before the drought event, whereas Aleppo pines showed growth decline irrespective of tree defoliation. At the end of the drought period, all species showed increased defoliation and a related reduction in the concentration of sapwood soluble sugars. Defoliation was constrained by the BAI of the previous 5 years and sapwood production. No specific wood‐inhabiting fungi were found in post‐drought declining trees apart from blue‐stain fungi, which extensively affected damaged Scots pines. Declining silver firs showed increases in BAI autocorrelation and variability prior to tree death. Synthesis. Early warning signals of drought‐triggered mortality seem to be species specific and reflect how different tree species cope with drought stress. Highly correlated declining growth patterns during drought can serve as a signal in silver fir, whereas changes in the content of sapwood soluble sugars are suitable vigour proxies for Scots and Aleppo pines. Longer growth and defoliation series, additional vigour parameters and multi‐species comparisons are required to understand and predict drought‐induced tree death.

Stress integrated tests and cytological analyses reveal Brassica villosa subsp. drepanensis seed quality decrease upon long-term storage

Under stress integrated germination test (SIGT), seeds undergo osmo-saline stresses, which enable to detect differences in vigour of long-term stored seeds with high germination percentage (G%). The quality of Brassica villosa subsp. drepanensis seeds stored in a genebank (at − 20°C for 16 years) was compared with seeds at harvest by standard germination tests (GT), SIGT and cytogenetic analysis. No differences were detected in G% and mean germination time under GT. Conversely, SIGT performed with NaCl − 0.9 MPa osmotic potential did not influence G% at harvest but reduced that of stored seeds, SIGT at − 1.4 MPa reduced G% of both. Cytogenetic analysis showed reduction of mitotic index, appearance of chromosomal aberrations and smaller nucleoli in stored seeds compared with harvest seeds germinated in water. SIGT at − 0.9 MPa had no effect on mitotic index, but increased chromosome aberrations and nucleoli number. SIGT at − 1.4 MPa inhibited G% of harvest and stored seeds, reduced mitoses in harvest and completely prevented it in stored seeds. The results indicate that GT does not faithfully reflect the quality of stored seeds, with misinterpretation of their vigour, whereas SIGT and cytogenetical parameters are sensitive, reliable and inexpensive methods for early prediction of genetic erosion in germplasm banks.

Automated estimation of leaf area index from grapevine canopies using cover photography, video and computational analysis methods

Background and Aims Monitoring of canopy vigour is an important tool in vineyard management to obtain balanced vines (vegetative vs reproductive organs). Leaf area index is the main parameter representing canopy vigour. Our aim was to test an automated computational method to obtain leaf area index and canopy vigour parameters from grapevines with digital photography and video analysis using MATLAB programming techniques for rapid data uptake and gap size analysis. Methods and Results The proposed method was tested against allometry at a Chilean experimental site planted with cv. Merlot. A temporal and spatial assessment of the method was also tested in a drought and drought/recovery experiment with cv. Chardonnay in the Riverland, South Australia. These data were geo-referenced and compared to the normalised difference vegetation index extracted from the WorldView-2 satellite images at a 2 m2 per pixel resolution. Conclusions The maximum leaf area index data obtained with cover digital photography and video analysis are an accurate, cost-effective and easy-to-use method to estimate spatial and temporal canopy LAI and structure when compared to standard measurements (allometry and plant canopy analyser). Significance of the Study This study has demonstrated that the method proposed is an accurate and inexpensive tool for application in experiments and by the industry to monitor spatio-temporal distribution of vigour.

Gamma sensitivity of forest plants of Western Ghats

Seeds of Artocarpus hirsutus Lam., Garcinia xanthochymus Hook., Saraca asoca Roxb., Rourea minor Gaertn., Pterocarpus marsupium Roxb., Terminalia chebula Retz., Aporusa lindleyana (Wt.) bail., Holoptelea integrifolia Roxb. and Oroxylum indicum (L.) Vent. were collected from different regions of Western Ghats and exposed to different doses of gamma radiation using Co-60 source. The effect of irradiation was examined on germination, growth and vigor parameters. Decrease in the germination and growth attributes with increased dose was observed in A. hirsutus, G. xanthochymus and S. asoca and thus indicating sensitivity of these plants to radiation. In contrast, enhancement in the germination (percentage), vigor and generation of leaves was observed for P. marsupium, T. chebula, H. integrifolia and O. indicum. These plants were classified as radiation tolerant because of the ability of their seedlings to successfully establish under radiation stress. R. minor and A. lindleyana were able to maintain viability up to 100 Gy dose, however, any further increase in the dose found to have negative effect.

Predicting the Longevity of Sesame Seeds under Short-Term Containerized Storage with Charcoal Desiccant

Seeds are characterized by rapid deterioration during storage under humid tropical conditions of high air temperature and relative humidity. Physiological changes that occur in seeds during storage are manifested as reduction in seedling vigor index, number of germination, percentage germination, speed of germination and rate of germination among others. This study aimed at prolonging the longevity of sesame seed through containerized storage with charcoal desiccant. Forty grams of sesame seeds was stored with varying amount of charcoal desiccant (0, 40, 80, 120, 160 and 200 g). The containerized seeds were then placed in a wooden cabinet with average ambient conditions of 29.8oC and 80% relative humidity, and stored for 12weeks. Samples were taken from storage at interval of two weeks and tested for seed viability and seedling vigor. Analysis of variance (ANOVA) was carried out on the data collected and treatment means were separated using Duncan’s Multiple Range Test (DMRT). Serial germination data were also subjected to probit analysis Research Article American Journal of Experimental Agriculture, 4(1): 1-11, 2014 2 in order to model sesame seed deterioration in storage. ANOVA results show that charcoal treatments were highly significant (P≤0.01) on all the seed viability and seedling vigour parameters evaluated. Storage time was also highly significant on all the parameters. However, interaction between seed treatment and storage time was not significant (P≥0.01) on seed germination and seedling vigour index. There were also statistical differences among the charcoal treatments and among the storage periods. Probit results indicate that seed preservation was optimal in seed treated with 200 g charcoal with seed half life (P50) of 13.19 weeks, and lowest seed deterioration rate (1/σ) of 0.1559. It is recommended that 200 g or more of dry charcoal should be adopted for short-term and mediumterm sesame seed treatment as it effectively maintained seed viability and seedling vigour during storage as compared to other treatments.

Does fire severity influence shrub resprouting after spring prescribed burning?

Prescribed burning is commonly used to reduce the risk of severe wildfire. However, further information about the associated environmental effects is required to help forest managers select the most appropriate treatment. To address this question, we evaluated if fire severity during spring prescribed burning significantly affects the resprouting ability of two common shrub species in shrubland under a Mediterranean climate in NW Spain. Fire behaviour and temperatures were recorded in tagged individuals of Erica australis and Pterospartum tridentatum during prescribed burning. The number and length of resprouted shoots were measured three times (6, 12 and 18 months) after the prescribed burning. The influence of a series of fire severity indicators on some plant resprouting vigour parameters was tested by canonical correlation analysis. Six months and one year after prescribed burning, soil burn severity (measured by the absolute reduction in depth of the organic soil layer, maximum temperatures in the organic soil layer and the mineral soil surface during burning and the post-fire depth of the organic soil layer) reduced the resprouting vigour of E. australis and P. tridentatum. In contrast, direct measurements of fire effects on plants (minimum branch diameter, duration of temperatures above 300 °C in the shrub crown and fireline intensity) did not affect the post-fire plant vigour.Soil burn severity during spring prescribed burning significantly affected the short-term resprouting vigour in a mixed heathland in Galicia. The lack of effects eighteen months after prescribed burning indicates the high resilience of these species and illustrates the need to conciliate fire prevention and conservation goals.

Improved performance of muskmelon (Cucumis melo) seeds with osmoconditioning

Seeds of muskmelon (<em>Cucuniis melo</em>) cultivars viz Pb. Hybrid and Pb. Sunehri were osmoconditioned with Polyethylene glycol (PEG) and KNO<sub>3</sub> solutions to enhance their performance at low temperature. Osmoconditioning both with PEG 6000 and KNO<sub>3</sub> increased per cent germination, speed of germination, vigour in terms of dry weight and length of the seedlings and root/shoot ratios. KNO<sub>3</sub> priming recorded more pronounced effects in all the above mentioned parameters. Other vigour parameters such as electrical conductance of seed leachates was decreased with osmoconditioning whi]e dehydrogenase activity was enhanced. Osmoconditioning resulted in increased activity of amylases.

Seed Invigoration Techniques to Improve Germination and Early Growth of Sunflower Cultivars

Sunflower (Helianthus annuus L.) is one of the most important oil crops worldwide. Due to high oil content, sunflower achens often posse's low germination and vigour. An effective pre-sowing treatment to enhance the germination and vigour is required. So it was imperative to develop suitable techniques in order to improve sunflower achen germination capacity. Achens priming is now a widely used commercial process that accelerates the germination rate and improves achenling uniformity in many crops. A laboratory study was conducted to find out the influence of achens priming treat- ments on germination and achenling vigour as well as some physiological characters of two sunflower cultivars (Giza 102 and Sakha 53). Achens priming using ascorbic acid at 75 mg/L and folic acid 20 mg/L recorded the maximum emergence percentage and minimum mean emergence time in Sakha 53 and Giza 102 cultivars, respectively as compared with unprimed achens. In most cases, priming strategies improved the achenling vigor in terms of shoot and root length and dry weights, and shoot to root ratio. Compared with control, in Sakha 53 cultivar, achenling vigour parameters were higher at 20 mg/L folic acid and 75 mg/L ascorbic acid for both for Giza 102 and Sakha 53, respectively. Moreover, all priming technology in- creased all physiological characteristics as compared with control. Therefore, it could conclude that achens primed with ascorbic acid or folic acid solution of may be used for sunflower achen invigoration.

Role of Relative Humidity in Processing and Storage of Seeds and Assessment of Variability in Storage Behaviour in Brassica spp. and Eruca sativa

The role of relative humidity (RH) while processing and storing seeds of Brassica spp. and Eruca sativa was investigated by creating different levels of relative humidity, namely, 75%, 50%, 32%, and 11% using different saturated salt solutions and 1% RH using concentrated sulphuric acid. The variability in seed storage behaviour of different species of Brassica was also evaluated. The samples were stored at 40 ± 2°C in sealed containers and various physiological parameters were assessed at different intervals up to three months. The seed viability and seedling vigour parameters were considerably reduced in all accessions at high relative humidity irrespective of the species. Storage at intermediate relative humidities caused minimal decline in viability. All the accessions performed better at relative humidity level of 32% maintaining seed moisture content of 3%. On analyzing the variability in storage behaviour, B. rapa and B. juncea were better performers than B. napus and Eruca sativa.

Relationship between physical and chemical parameters for four commercial grape varieties from the Bierzo region (Spain)

Four Vitis vinifera L. varieties (Mencía, Cabernet Sauvignon, Tempranillo and Merlot) were evaluated for viticultural characteristics in the vineyards of a winery located in the Bierzo Protected Designation of Origin (PDO) region of León in Spain. Must parameters (total soluble solids, pH, titratable acidity, total phenolic content, colour intensity and colour tonality), production parameters (mean berry weight, yield, number of clusters and mean cluster weight) and vigour parameters (shoot pruning weight, Ravaz index, number of shoots, mean weight of shoots, mean length of shoots, mean number of buds per shoot, mean length of internodes, and mean diameter of shoots) were measured during four seasons (2007, 2008, 2009 and 2010). The grape samples were taken 3–5 days after harvest with similar degree brix levels. Must and production parameters differed significantly among varieties and seasons. Although total soluble solids and pH values differed significantly between varieties, the range for the two measurements was small. Mencía yielded the highest grape production while Tempranillo had the lowest, with differences due primarily to mean berry weight and mean cluster weight. Tempranillo and Cabernet had the highest vigour values. Ravaz index values were highest (>10) for Mencía and lowest (<4) for Tempranillo, Merlot and Cabernet. Mencía was the variety best suited to the growing area and the preferential variety for the wines made in the Bierzo PDO. Tempranillo adapted most poorly to the growing conditions. The varietal evolution trend was sharper than the temporal evolution trend.

Assessment of the spatial variability of anthocyanins in grapes using a fluorescence sensor: relationships with vine vigour and yield

The use of new, rapid and non-invasive sensors in the field allows the collection of many observations which are necessary to assess the spatial variability of berry composition. The aim of this work was to study the spatial variability in anthocyanin content in grapes and to quantify its relationship with the vigour and yield in a commercial vineyard. The study was conducted in a Tempranillo (Vitis vinifera L.) vineyard (Navarra, Spain). A new, hand-held, non-destructive fluorescence-based proximal sensor was used for monitoring the anthocyanin content in grapes at veraison and harvest. Yield, vine vigour, spectral (normalized difference vegetation index and plant cell density) and chlorophyll (SPAD and simple chlorophyll fluorescence ratio) parameters were measured. Yield variability within the vineyard was the largest of all the parameters. Fluorescence-based anthocyanin indices were less variable at harvest than at veraison. The vigour parameters (main shoot length, total shoot length and shoot pruning weight) were positively correlated to yield; the chlorophyll and the spectral indices were negatively correlated with berry anthocyanin production. The correlations between vigour, yield and anthocyanin content in grapes varied substantially in time and space across the vineyard.

Bacillus subtilis bacteriocin Bac 14B with a broad inhibitory spectrum: Purification, amino acid sequence analysis, and physicochemical characterization

Bacillus subtilis strain 14B was used to produce a novel antimicrobial peptide (bacteriocin) called Bac 14B. Pure bacteriocin was obtained after heat and acidic treatments (80°C and pH 4), precipitation by ammonium sulfate, and chromatography on Sephadex G-50 and Mono Q Sepharose columns. Based on MALDI-TOF mass spectrometry analysis, purified Bac 14B is a monomer protein with a molecular mass of 20110.13 Da. N-terminal sequencing allowed for the straightforward identification of its first 12 residues, which were of a pure bacteriocin. It also revealed that this bacteriocin contained a unique sequence, namely M-L-K-A-N-L-Q-N-P-L-N-A, suggesting the identification of a novel compound. Bac 14B was stable for 1 h at temperatures up to 80°C and pH of 4 ∼ 8. It also proved sensitive to various proteases, which demonstrated its protein nature. Bac 14B displayed a bacteriolytical mode of action and a broad range of inhibitory spectra toward Gram-positive and -negative pathogens. Interestingly, based on conventional agronomic seed vigor parameters, the application of Bac 14B (500 activity units/mL) to various crops revealed that this bacteriocin was a potent exogenous enhancer of growth that stimulated the seedling vigor of tomatoes and muskmelons. Compared to those of the control, the germination percentage, shoot weight, shoot height, and root length were all significantly enhanced in Bac 14B-treated plant seeds. Bac 14B also exhibited effective disinfectant properties against a wide range of seedborne diseases and significant effects on the control of damping off diseases, particularly at the pregermination stage. It also proved to be effective against root rot diseases caused by Alternaria solani and other bacterial seedborne pathogens such as wilt diseases. The findings indicate that Bac 14B is the first B. subtilis-produced bacteriocin ever reported to exhibit such promising biological properties.

Evaluation of sowing value and vigor of dressed grain of winter triticale and rye depending on the cultivar and period of storageOcena wartości siewnej i wigoru zaprawionego ziarna pszenżyta ozimego i żyta w zależności od odmiany i okresu jego przechowywania

Summary The two, two-factorial laboratory experiments were carried out at the Agronomy Depa rtment of Poznan University of Life Sciences. The first factor of first experiment considered were winter triticale cultivars: Fidelio, Woltario, and in the second experiment winter rye cultivars: Arant, Gradan, Nawid. Cereal grain was dressed with fludioxonil (winter triticale) and karboxin + thiram (winter rye). The second experimental factor was a storage period of grain. The grain was evaluated directly after dressing and 180 days after the treatment. The results of the studies revealed that the cultivar Fidelio was characterized by a higher sowing value of grain and vigor than the cultivar Woltario. Six-month storage period of dressed grain of winter triticale caused a significant reduction in grain germination capacity, a simultaneous increase in the number of dead grains as well as a deterioration of grain vigor parameters. In the experiment with rye the best of sowing value showed the cultivar Nawid and the worst one the cultivar Arant. A half year storage period decreased germination capacity of the dressed grain, but did not significantly influence its vigor.