A phenological scale for the development of Gladiolus

A staging system for development of gladiola (Gladiolus × grandiflorus) that relies on simple, visual, non‐destructive criteria is proposed. Four field trials were conducted during the spring 2010, autumn/winter 2011 and winter 2011 at Santa Maria, RS, Brazil, with different gladiola cultivars, in order to observe the developmental stages of the above‐ground parts and their dry matter. The developmental cycle, which starts at dormant corm and ends with plant senescence, is divided into four developmental phases: dormancy phase, sprouting phase (from filiform roots appearance to sheaths appearance), vegetative phase (from emergence of the first leaf tip to emergence of the final leaf tip on the stem) and reproductive phase (from heading to plant senescence). The developmental stages that were identified during the dormancy phase and during the sprouting phases are coded as S stages: S0 = dormant corm, S1 = appearance of roots, S2.1 = first sheath, S2.2 = second sheath and S2.3 = third sheath. Vegetative phase is coded as V stages: VE = emergence of the sheaths above ground, V1 = first leaf, V2 = second leaf, Vn = nth leaf and VF = flag leaf. Leaf tip is the marker for V1–VF. The developmental stages during the reproductive phases are coded as R stages: R1 = heading, R2 = blooming, R3 = onset of flowering, R4 = end of anthesis, R5 = end of florets senescence and R6 = plant senescence (leaves and floret axis are brown). Sub‐stages have also been assigned between R1 and R2 and between R3 and R4. Illustrations (photographs) of each developmental stage taken from field pot‐grown plants are provided and the proposed scale was tested with field observations. These criteria are straight forward and allow for quick determination of development stage. This system can be used by both farmers and for experimental trials.     

A comparison of methods to estimate cross-environment genetic correlations

Advanced techniques for quantitative genetic parameter estimation may not always be necessary to answer broad genetic questions. However, simpler methods are often biased, and the extent of this determines their usefulness. In this study we compare family mean correlations to least squares and restricted error maximum likelihood (REML) variance component approaches to estimating cross-environment genetic correlations. We analysed empirical data from studies where both types of estimates were made, and from studies in our own laboratories. We found that the agreement between estimates was better when full-sib rather than half-sib estimates of cross-environment genetic correlations were used and when mean family size increased. We also note biases in REML estimation that may be especially important when testing to see if correlations differ from 0 or 1. We conclude that correlations calculated from family means can be used to test for the presence of genetic correlations across environments, which is sufficient for some research questions. Variance component approaches should be used when parameter estimation is the objective, or if the goal is anything other than determining broad patterns.     

Experimental kS estimation: A comparison of methods for Corynebacterium glutamicum from lab to microfluidic scale

Knowledge about the specific affinity of whole cells toward a substrate, commonly referred to as k_S, is a crucial parameter for characterizing growth within bioreactors. State-of-the-art methodologies measure either uptake or consumption rates at different initial substrate concentrations. Alternatively, cell dry weight or respiratory data like online oxygen and carbon dioxide transfer rates can be used to estimate k_S. In this work, a recently developed substrate-limited microfluidic single-cell cultivation (sl-MSCC) method is applied for the estimation of k_S values under defined environmental conditions. This method is benchmarked with two alternative microtiter plate methods, namely high-frequency biomass measurement (HFB) and substrate-limited respiratory activity monitoring (sl-RA). As a model system, the substrate affinity k_S of Corynebacterium glutamicum ATCC 13032 regarding glucose was investigated assuming a Monod-type growth response. A k_S of <70.7 mg/L (with 95% probability) with HFB, 8.55 ± 1.38 mg/L with sl-RA, and 2.66 ± 0.99 mg/L with sl-MSCC was obtained. Whereas HFB and sl-RA are suitable for a fast initial k_S estimation, sl-MSCC allows an affinity estimation by determining t_D at concentrations less or equal to the k_S value. Thus, sl-MSCC lays the foundation for strain-specific k_S estimations under defined environmental conditions with additional insights into cell-to-cell heterogeneity.     

Phenological behaviour of Parthenium hysterophorus in response to climatic variations according to the extended BBCH scale

Considering the importance of ecological and biological traits in imparting invasive success to the alien species, the phenological behaviour of an alien invasive weed Parthenium hysterophorus was documented according to the extended BBCH scale in four different seasons. A phenological calendar was prepared using both two‐ and three‐ digit coding system, precisely describing the developmental stages of the weed. The phenological documentation is further supplemented with the dates corresponding to a particular growth stage, pictures of the representative growth stages and meteorological data of all the four seasons. Results revealed that the phenology of the weed altered in response to the changing temperature and humidity conditions but no apparent climatic condition could inhibit its germination or flowering. However, the emergence of inflorescence was highly sensitive to the temperature/photoperiodic conditions. Variations in the phenological traits of P. hysterophorus with changing environmental conditions explain the acclimatisation potential of the weed permitting its vast spread in the non‐native regions. Since the given phenological illustrations are accurate, unambiguous and coded as per an internationally recognised scale, they could be exploited for agronomic practices, weed management programmes, and research purposes.     

Phenological growth stages of jackfruit (Artocarpus heterophyllus) according to the extended BBCH scale

Jackfruit, the largest known edible fruit bearing tree, is one of the important fruit crops of India. It exhibits wide range of diversity with respect to fruit character and bulb quality. It is an important component of homestead garden because of its multifarious uses (dessert, vegetable and pickle) and high nutritive value. In spite of high food value and market potential, jackfruit is one of the poorly researched crops and there is a dearth of information about its phenology. The present study defines phenological stages of jackfruit according to the extended BBCH (Biologische Bundesantalt, Bundessortenamt und Chemische Industrie) scale using three‐digit numerical system. Eight principal growth stages, namely bud development (stage 0), shoot development (stage 1), leaf development (stage 3), specialised reproductive shoot development (stage 4), reproductive development (stage 5), flowering (stage 6), fruit development (stage 7) and fruit maturation (stage 8) have been described. A total of 42 secondary growth stages have been described and defined. In this study, bearing and non‐bearing footstalks as well as male and female phases have been defined separately. The study will act as an effective tool for providing a consensual unified approach for standardisation of phenophases, as well as for efficient orchard management for ensuring higher yield and fruit quality. The scale may also be effectively used for characterisation and adaptation of germplasm and assessment of climatic impact on crop phenology.     

热带季节雨林林冠碳通量不同校正方法的比较分析

利用西双版纳热带季节雨林2003年3月1～9日的CO₂和水汽通量数据,比较了不同校正方法的差异.结果表明,对季节雨林林冠碳通量观测数据进行校正是必要的,但不同校正方法所起的作用有所差异;昼间WPL校正的作用最大,虚温校正的作用最小;t检验证明,经WPL修正后的碳通量值与基准值、无显著差异;聚类分析表明,进行自然风3次旋转校正有利于数值精度的提高.夜间是自然风旋转校正的贡献最大、虚温校正贡献最小;t检验表明,经过WPL修正和平面旋转校正及其组合得到的碳通量值与基准值均有显著差异;而经包含有自然风旋转校正处理后的碳通量值与基准值均无显著差异;聚类分析表明,经过自然风坐标旋转后,再进行WPL修正,有利于数值精度的提高.     

Phenological growth stages of Indian jujube (Ziziphus mauritiana Lamk.) according to the BBCH scale

Indian jujube (Ziziphus mauritiana Lamk.) has been recognised as an underutilised plant worthy of further research and development by the Indian National Genetic Resources Programme and the International Centre for Underutilised Crops, UK. It is an important fruit crop of the hot arid regions in India as it forms an integral part of the life of the locals as a source of nutrition, fodder (leaves), fuel (pruned wood) and it has several ethnobotanical uses. In this study, 8 of the 10 principal growth stages based on the existing Biologische Bundesantalt, Bundessortenamt und Chemische Industrie (BBCH) scale were used to describe Indian jujube. These growth stages were vegetative bud development (Stage 0), leaf development (Stage 1), shoot development (Stage 3), inflorescence development (Stage 5), flower development (Stage 6), fruit development (Stage 7), fruit maturity (Stage 8) and senescence or beginning of dormancy (Stage 9). The phenological BBCH scale for Indian jujube can be used to guide the growers as to when to carry out orchard management practices such as canopy training and pruning, nutrient and water application, pest and disease control and post‐harvest processing.     

Evapotranspiration model comparison and an estimate of field scale Miscanthus canopy precipitation interception

The bioenergy crop Miscanthus × giganteus has a high water demand to quickly increase biomass with rapid canopy closure and effective rainfall interception, traits that are likely to impact on hydrology in land use change. Evapotranspiration (ET, the combination of plant and ground surface transpiration and evaporation) forms an important part of the water balance, and few ET models have been tested with Miscanthus. Therefore, this study uses field measurements to determine the most accurate ET model and to establish the interception of precipitation by the canopy (C_i). Daily ET estimates from 2012 to 2016 using the Hargreaves–Samani, Priestley–Taylor, Granger–Gray, and Penman–Monteith (short grass) models were calculated using data from a weather station situated in a 6 ha Miscanthus crop. Results from these models were compared to data from on‐site eddy covariance (EC) instrumentation to determine accuracy and calculate the crop coefficient (K_c) model parameter. C_i was measured from June 2016 to March 2017 using stem‐flow and through‐flow gauges within the crop and rain gauges outside the crop. The closest estimated ET to the EC data was the Penman‐Monteith (short grass) model. The K_c values proposed are 0.63 for the early season (March and April), 0.85 for the main growing season (May to September), 1.57 for the late growing season (October and November), and 1.12 over the winter (December to February). These more accurate K_c values will enable better ET estimates with the use of the Penman‐Monteith (short grass) model improving estimates of potential yields and hydrological impacts of land use change. C_i was 24% and remained high during the autumn and winter thereby sustaining significant levels of canopy evaporation and suggesting benefits for winter flood mitigation.     

A comparison of hydrocortisone and triamcinolone inhibition of scale and feather development

Hydrocortisone (30-40 micrograms on day 10) and triamcinolone (10-20 ng on day 7-8) both inhibit or alter morphogenesis of scales and feathers. However, there are marked temporal and region-specific differences in the effects induced by these two glucocorticoids. Triamcinolone (TAC) is most teratogenic on day 7 or 8, inhibiting formation of spurs and feathers and inducing club feather formation. Hydrocortisone is most teratogenic later in development, on day 10. Unique hydrocortisone-induced responses are complete inhibition of scutellate scale formation, bent feathers, and apteria around the external auditory meatus. Altered synthesis of keratin polypeptides follows inhibition of scale morphogenesis by hydrocortisone and TAC. These in vivo data suggest that heterogeneity of glucocorticoid binding occurs in embryonic chick metatarsal skin. Survival data indicate that TAC is 2,000 times more embryotoxic than hydrocortisone.