of least seed viability percentages even drying the seeds till recommended extent
(20%) may arise due to environmental factors, from seed development to seed
drying, affecting the tolerance of seeds against desiccation and liquid nitrogen
[122, 123].
Geostatic methods (e.g., spatial variability) have also been used to typify the
physiological study of coffee seeds. Various studies [125–129] also successfully
define the region for the quality seedling production. Despite the advances in
quantitative soil mapping techniques, most soil maps continue to be produced
using conventional techniques. The usefulness for decision making of such maps
is restricted [34]. Furthermore, as discussed in Sect. 2.1, most of genetic and
breeding improvement programs only focus on the yield, yield stability, cup quality,
and insect pest resistant coffee varieties; little attention was paid to the genetic
transformation of existing coffee cultivars for production of desiccation tolerant
coffee seeds genotypes. The least amount of works available focus only on the
non-Arabica coffee cultivars, e.g., C. pseudozanguebariae X Coffea liberica var.
dewevrei [122, 123]. The backcross progenies of these least variable parents showed
a transgression in the course of most delicate parent without a discrete level of
desiccation tolerance. Further, seed desiccation tolerance is a declared quantitative
polygenic or multifactorial trait, but initial seed viability or moisture [130], initial
desiccation rate seed size, and tree fertility not affect the understudy trait [123]. The
mapping of QTLs responsible for desiccation tolerance is still underway after their
successful application on other important agricultural crops. In genus Coffea, most
of the discovered genetic accessions belong to the C. robusta and desiccation
tolerance of this species supposed to be equivalent to C. arabica. The simplified
methods and protocols from simple cryopreservation to inheritance in breeding and
from breeding to molecular level (QTLs mapping) are also now available. So it is
now prerequisite and vital to thoroughly explore globally discovered genotypes of C.
robusta along C. arabica to finally desiccation tolerant seeds hybrid. If this milestone is achieved, it will have a great impact not only on research and development
but also on the cheap preservation of seeds at commercial level for the quality
seedling production.
2.4
Soil and Fertilization
Among various reasons of lower cup quality of coffee, under or no fertilization of
coffee fields is also a leading factor for this cause. A study by Sivetz and Foote [131]
showed that nutrient deficiencies may decrease cup flavor. On the other hand, Pochet
[132] demonstrated a very clear and positive link between the organoleptic qualities
and low soil fertility. To deal with low soil fertility issue, the conventional ways of
fertilization are also same for coffee fields, i.e., organic and inorganic or mineral
fertilization. This section is also highly linked with topographic conditions, management practices, organic matter and herbicide applications, shade, rainfall or
irrigation, planting and intercropping schemes, and agroforestry systems which
collectively determine the fate of soil by affecting its organic matter contents
664
A. Hameed et al.
(20%) may arise due to environmental factors, from seed development to seed
drying, affecting the tolerance of seeds against desiccation and liquid nitrogen
[122, 123].
Geostatic methods (e.g., spatial variability) have also been used to typify the
physiological study of coffee seeds. Various studies [125–129] also successfully
define the region for the quality seedling production. Despite the advances in
quantitative soil mapping techniques, most soil maps continue to be produced
using conventional techniques. The usefulness for decision making of such maps
is restricted [34]. Furthermore, as discussed in Sect. 2.1, most of genetic and
breeding improvement programs only focus on the yield, yield stability, cup quality,
and insect pest resistant coffee varieties; little attention was paid to the genetic
transformation of existing coffee cultivars for production of desiccation tolerant
coffee seeds genotypes. The least amount of works available focus only on the
non-Arabica coffee cultivars, e.g., C. pseudozanguebariae X Coffea liberica var.
dewevrei [122, 123]. The backcross progenies of these least variable parents showed
a transgression in the course of most delicate parent without a discrete level of
desiccation tolerance. Further, seed desiccation tolerance is a declared quantitative
polygenic or multifactorial trait, but initial seed viability or moisture [130], initial
desiccation rate seed size, and tree fertility not affect the understudy trait [123]. The
mapping of QTLs responsible for desiccation tolerance is still underway after their
successful application on other important agricultural crops. In genus Coffea, most
of the discovered genetic accessions belong to the C. robusta and desiccation
tolerance of this species supposed to be equivalent to C. arabica. The simplified
methods and protocols from simple cryopreservation to inheritance in breeding and
from breeding to molecular level (QTLs mapping) are also now available. So it is
now prerequisite and vital to thoroughly explore globally discovered genotypes of C.
robusta along C. arabica to finally desiccation tolerant seeds hybrid. If this milestone is achieved, it will have a great impact not only on research and development
but also on the cheap preservation of seeds at commercial level for the quality
seedling production.
2.4
Soil and Fertilization
Among various reasons of lower cup quality of coffee, under or no fertilization of
coffee fields is also a leading factor for this cause. A study by Sivetz and Foote [131]
showed that nutrient deficiencies may decrease cup flavor. On the other hand, Pochet
[132] demonstrated a very clear and positive link between the organoleptic qualities
and low soil fertility. To deal with low soil fertility issue, the conventional ways of
fertilization are also same for coffee fields, i.e., organic and inorganic or mineral
fertilization. This section is also highly linked with topographic conditions, management practices, organic matter and herbicide applications, shade, rainfall or
irrigation, planting and intercropping schemes, and agroforestry systems which
collectively determine the fate of soil by affecting its organic matter contents
664
A. Hameed et al.