Step 1: Understanding the Concept:
Standard apple (Malus domestica) varieties generally require cold temperatures during winter (typically \( 800 \) to \( 1500 \) chilling hours below \( 7.2^\circ\text{C} \)) to break bud dormancy.
For subtropical and warm-temperate regions, low-chilling cultivars have been bred to produce quality fruit with minimal chilling requirements (under \( 300 \) hours).
Step 2: Detailed Explanation:
Let us evaluate the options for the apple cultivar 'Tamar':
Option (A): 'Tamar' is a low-chilling apple cultivar.
It is well-adapted to warm subtropical climates where winter temperatures are mild.
This statement is true.
Option (B): 'Tamar' was developed and selected in Israel (not South Africa), along with other famous low-chilling cultivars like 'Anna' and 'Michal'.
Therefore, stating that it originated from South Africa is incorrect, making this the correct answer for the "not true" question.
Option (C): The fruits of 'Tamar' are medium to large, crisp, and have a good, sweet, aromatic flavor profile, which makes this statement true.
Option (D): In warm subtropical environments, 'Tamar' ripens early in the summer, typically during the month of July, making this statement true.
Step 3: Final Answer:
The statement "Originated from South Africa" is not true for the Tamar apple.