The effect of deficit irrigation on water relations, growth, and fruit quality of "Braeburn" apples (Malus domestica Borkh.) growing in lysimeters : a thesis presented in partial fulfilment of the requirements for the degree of Master of Applied Science at Massey University

This project investigated the feasibility and practicality of using deficit irrigation (DI) at different times of the growing season on water relations, growth and fruit quality of 'Braeburn' apples grown in lysimeters. Five-year-old trees on MM. 106 rootstock were subjected to three irrigation treatments in a completely randomised design. The treatments were: Well-watered control (C), deficit irrigated for the entire season (ED), and deficit irrigated late in the season (LD) from 102 days after full bloom (DAFB) to harvest. Both ED and LD trees developed a lower predawn and midday leaf water potential than C trees. For LD and ED trees towards the end of growing season, reduction occurred in the photosynthesis (Pn), stomatal conductance (gs), and the rate of transpiration. The reduction in Pn was caused by stomatal and non-stomatal factors. Deficit irrigation caused an increase in canopy temperature (Tc) and canopy-air temperature difference (Tc-Ta) in ED and LD. Fruit growth was not affected by DI although shoot growth and increase in trunk circumference were significantly reduced under DI. Deficit irrigation also reduced mean fruit weight at harvest as well as return bloom. Deficit irrigation increased the concentration of fruit soluble solids and volatiles, decreased that of N, and did not have any effects on the concentration of P, Ca2+, Mg2+, and K+. The ED and LD treatments resulted in more advanced fruit maturity based on higher ethylene production and TSS concentration. Firmness was higher in LD and ED fruit than the C fruit after 12 weeks of storage at 1 °C. This study showed that water deficit late in the season may be used in apple production with improved fruit quality in terms of increased TSS. firmness in storage, and higher volatiles without adversely affecting on fruit size

Octant Degeneracy, Quadrant of leptonic CPV phase at Long Baseline Neutrino Experiments and Baryogenesis

In a recent work by us, we have studied, how CP violation discovery potential can be improved at long baseline neutrino experiments (LBNE/DUNE), by combining with its ND (near detector) and reactor experiments. In this work, we discuss how this study can be further analysed to resolve entanglement of the quadrant of leptonic CPV phase and Octant of atmospheric mixing angle $\theta_{23}$, at LBNEs. The study is done for both NH (Normal hierarchy) and IH (Inverted hierarchy), HO (Higher Octant) and LO (Lower Octant). We show how baryogenesis can enhance the effect of resolving this entanglement, and how possible values of the leptonic CP-violating phase $\delta_{CP}$ can be predicted in this context. With respect to the latest global fit data of neutrino mixing angles, we predict the values of $\delta_{CP}$ for different cases. In this context we present favoured values of $\delta_{CP}$ ($\delta_{CP}$ range at $\geq$ 2$\sigma$ ) constrained by the latest updated BAU range and also confront our predictions of $\delta_{CP}$ with an up-to-date global analysis of neutrino oscillation data. We find that some region of the favoured $\delta_{CP}$ parameter space lies within the best fit values around $\delta_{CP} \simeq 1.3\pi-1.4 \pi$. A detailed analytic and numerical study of baryogenesis through leptogenesis is performed in this framework in a model independent way.Comment: 14 pages, 5 figures, 2 Tables, New Analysi

Compatibility of A4A_{4} Flavour Symmetric Minimal Extended Seesaw with (3+1)(3+1) Neutrino Data

Motivated by the recent resurrection of the evidence for an eV scale sterile neutrino from the MiniBooNE experiment, we revisit one of the most minimal seesaw model known as the minimal extended seesaw that gives rise to a $3+1$ light neutrino mass matrix. We consider the presence of $A_4$ flavour symmetry which plays a non-trivial role in generating the structure of the neutrino mass matrix. Considering a diagonal charged lepton mass matrix and generic vacuum alignments of $A_4$ triplet flavons, we classify the resulting mass matrices based on their textures. Keeping aside the disallowed texture zeros based on earlier studies of $3+1$ neutrino textures, we categorise the remaining ones based on texture zeros, $\mu-\tau$ symmetry in the $3\times3$ block and hybrid textures. After pointing out the origin of such $3+1$ neutrino textures to $A_4$ vacuum alignments, we use the latest $3+1$ neutrino oscillation data and numerically analyse the texture zeros and $\mu-\tau$ symmetric cases. We find that a few of them are allowed from each category predicting interesting correlations between neutrino parameters. We also find that all of these allowed cases prefer normal hierarchical pattern of light neutrino masses over inverted hierarchy.Comment: 46 pages, 8 figures, 21 table